How Much Does April Matter?

                                      HOW MUCH DOES APRIL MATTER ?

April provides the first hard evidence of what may be in store for the new season. But like any other single month, it usually has some conspicuously extreme results.  Typically 40% of all teams start notably well (.600 +)  or poorly (.400 minus) where by season’s end only 12% of all teams are at those outer edges of win percentage.  With 85% of the season to go, plenty of time remains for fates to change.  Or do they really change that much ?        This study focuses on the April records of all teams from 2000-2017 compared to their post-April results and odds for making the playoffs.  Two issues are addressed.  First, how closely teams’ remaining five months have corresponded to their Aprils and second, what effect April has had on teams’ playoff chances.


April records of all teams from 2000-2017, were divided into six win % categories: Excellent (.650+ win % ), Good (.550 – .650), Slightly Positive  (.500 – .549), Slightly Negative (.450-.499),  Weak (.350 -.449) and Poor (below .350).   Teams in each April win category were compared to their post-April and full season win/loss percentages. The percentage of teams in each April category who played at playoff level (.580), contention level (.540+) or near-contention (.500) after April were also measured as well as the percentage of teams in each April win category who made the playoffs.  Following are the results:

April W/L               # April Win % Last 5 month Full Yr .580+ last 5 .540+ Last 5 .500+ Last 5 Made Playoffs Pct of All Pct of Playoff
Category Teams Average Win % Win % Months Months Months Teams Teams
.650+ 60 0.688 0.535    0.558 25% 53% 72% 60% 11% 23%
.550-.649 119 0.595 0.519 0.530 18% 44% 65% 43% 22% 33%
.500-.549 104 0.519 0.510 0.511 19% 37% 55% 33% 19% 22%
.450-.499 75 0.472 0.495 0.491 11% 29% 48% 20% 14% 10%
.350-.450 126 0.409 0.484 0.473 11% 25% 37% 14% 23% 11%
under.350 56 0.305 0.445 0.424 4% 7% 23% 4% 10%    1%


Each level of April performance has had better last 5 months performance and playoff chances than the level immediately below it. Contrasts between the top 1/3 and bottom 1/3 April teams are quite significant.  Two thirds of teams who’ve started well (.550 +) remain near contention by playing  .500 + ball afterward and roughly half make the playoffs.  Only one third of teams with .449 or worse Aprils play .500+ thereafter and just 9 % of these early strugglers have made the playoffs. Nearly 4 of every 5 of all playoff teams were .500+ or better in April and less than 1 in 10 playoff teams started .425 or worse. April has done a good job of quickly identifying contenders and non-contenders.

Much of that is due to April records strongly relating to prior season results. Current full season records also have had solid resemblance to prior full season records. So April simply confirms that many (if not most) teams are headed for the same general fate as last year. While these are generally reliable maxims, they’re hardly infallible. Many teams do change fortunes and sometimes April wrongly suggest things will stay the same.   Likewise April often may indicate a change is coming in the current season and it doesn’t materialize.   That will be explored next – just how often does April “fool” ?


Roughly 3 in 8 teams had more than .100 pt change in their April v. rest of season (ROS) win percentage.          For teams who start extremely well or poorly, even huge April v. ROS differentials haven’t change their season’s destinies. 2003 Yankees started the year at .769 win %  but played “only” .596 ball the rest of the way and won over 100 games.  Conversely a .260 point jump in win % for the 2000 Tigers over the last 5 months still didn’t push them over .500 on the season. But for a significant number of teams the last 5 months can wash out much of the good or bad April does. Hot starters fall apart and teams buried in April can rise from the ashes.

For determining both the amount and type of April deception the logical starting point is prior year records. Fully 70 % of teams with 90+ wins the prior year have .500 + Aprils v. 37% for teams with 69 minus wins. Since so many teams tend to have Aprils which are “characteristic” of their prior season , measuring the true amount of “April deception” can be done from two angles: 1 – How many Aprils “characteristic” of last year give true v. false signals of another similar season ?  2 – How often do “uncharacteristic” Aprils end up being true v. false signals of a better or worse year ?

 1st – How reliable are “characteristic” Aprils.  The following chart illustrates this

Prior Yr Wins April Win % # teams % win 90+ % win 81 + % in Playoffs
90 + Wins .520 + 83     64 %    84%    62%
80 -89 Wins .520 + 71     48 %    76 %    49 %
70 -79 Wins .499 minus 73       5 %    22 %      7 %
Below 70 Wins .499 minus 65       3 %    6 %      6 %


As can be seen, prior year good teams (90+ wins) with good Aprils have had twice the chances of making the playoffs as an average team (30%). On the other side, prior year sub-.500 teams with sub-.500 Aprils have had very little chance of making postseason. Only 9 of 138 such teams have overcome their bad starts.   The percentage of teams finishing above .500 is also remarkably different.   80 % of good teams with good Aprils end up plus .500 on the year, where a mere 14 % of bad teams with bad Aprils do. “Characteristic” Aprils are highly reliable indicators of either continued contention or non-contention.    

“Highly reliable” does not mean “perfect”. The 90+ game winner/good April formula didn’t work for  defending world champions 2004 Marlins, 2013 Giants nor defending NL West champion 2008 D-Backs or 2005 Dodgers.  Nor did bad team/bad April deter the 2015 Rangers, 2011 D-Backs, and two Rockies teams (2009, 2007) plus the 2007 Cubs from rising up and making the playoffs.  But these are exceptions.

Applying these principles of “characteristic” Aprils to 2018 would bode well for the Red Sox, Yankees, Astros, Cubs and Diamondbacks. It would not for the Tigers, Rangers, Marlins, Padres, White Sox, Orioles, Royals and Reds.  With only 1 in 15 former sub-.500 /sub-.500 April teams having made the playoffs historical odds would indicate that none of the above eight teams will either.  Of course these clubs weren’t expected to contend but neither were the Braves, Phillies, Pirates, and Mets who were also bad teams from last year.  The difference is that latter four teams have had good Aprils.  So what do their “uncharacteristic” Aprils mean ?

 How often do “uncharacteristic” Aprils send true or false signals of change ?

After a surprising start in April many teams revert to their “true selves” (good or bad) in the last 5 months. But some percentage of uncharacteristic Aprils often correctly signal changes in a team’s fortunes. This time the data is parsed more finely to show where false and true indicators of change may appear.

Prior Yr Wins April Win % % Win 90+ % Win 81+ % in Playoffs
90 + Wins .401-.499   26 %    77 %     29 %
90+   Wins .399 minus   14 %    43 %    21 %
80 -89 Wins .401-.499   20 %    43 %    25 %
80 -89 Wins .399 minus   10 %    28 %    10 %
70 -79 Wins .600 +   39 %    72 %    44 %
70 -79 Wins .500 -.599   22 %    51 %    25 %
Below 70 Wins .600 +   18 %    64 %    18 %
Below 70 Wins .500 -.599     7 %    22 %    15 %


“Uncharacteristic” April at the extreme ends tend to be fairly accurate in signaling real change, particularly changes for the worse.  Very bad sub-.400 Aprils by former 81+ winners have shown that most are in trouble that season.    Nearly 60 % fail to achieve even a .500 season and only 15 % make the playoffs.  Some 90+ winners (21%)  with below .400 Aprils get off the mat and still make playoffs.  But that contrasts sharply with their prior year 90+ winning brethren who start April at .520 + and have made the playoffs 62% of the time.

What about extremely strong Aprils from previously bad teams ? Prior 70-79 winners who play .600 + in April have done quite well as 44 % have made the playoffs.  One caution, however, is small sample size as only 14 teams fall into this category. For really bad prior year teams (70 wins and below)  who start .600+ most achieved .500 seasons and 1 in 5 made the playoffs. This includes some notable turnarounds:  2000 Cardinals, 2000 White Sox, 2006 Tigers, 2012 Orioles, 2013 Red Sox, 2015 Astros, 2015 Cubs, 2017 Rockies, 2017 D-Backs.    Of course, excitement over great Aprils by prior bad teams should be tempered by the fact that most still have missed the playoffs. This may apply to expectations raised by the start of the 2018 Mets.  Although the 2015-2016 Mets were playoff teams so it’s quite possible their strong April 2018 could be a legitimate sign of revival.  Teams who gained 15 or more wins over the prior year showed an average of 120 points jump in April v. prior year win %.  The Mets have jumped 220 points.

Mildly uncharacteristic Aprils send wrong signals of change more often than not. Which is logical as a 65 game winner who goes 14-13 in April has shown less transformative evidence than one who’s 18-9. Nor has a former 100 game winner with a 12-13 April shown the same reason for concern as a 7 -18 start might.   Only 22 % of “below 70” teams with .500-.599 Aprils finished over .500. Former 70-79 winners with decent .500-.599 Aprils have upped their playoff odds but only to a subpar 20%. Seven teams fit this description in  2018 – Mariners, Pirates, Phillies, A’s, Braves, Blue Jays, Giants.  History says 1 will make it, 2 would be very optimistic.

However, one type of mildly uncharacteristic April is noteworthy. While previous 90+ winners with modestly bad .400-.499 Aprils still have a high recovery rate (77 % end up over .500) they’ve had a big drop in playoff odds. Only 29% make it after such starts.  That is not good news for 2018 Dodgers, Nationals or Twins whose goal is to make the playoffs.  Which brings up the next issue – how does April influence playoff chances ?


One old adage is “you can’t win the pennant in April but you can lose it”. While there is definite truth in this, April has the fewest games of any month, and still leaves ample time to recover. The 2001 Oakland A’s had a miserable 8 -17 April but went on to win 102 games.  That said, they were the only sub-.400 April team to win 100 + games and only one of 8 teams who started that poorly and still made the playoffs.   Another 10 such bad start teams played the rest of the season at contender levels (.540+ ) yet failed to make the playoffs and their poor Aprils were instrumental in that.

While it is clearly possible to recover from a weak start, bad Aprils leave a diminished margin of error. Two-thirds of all playoff teams start the year solidly (.530+ ), the vast majority (78%) are at least .500 + and fully 95 % of all playoff teams have avoided disastrous (sub. 400) Aprils.   Teams who’ve stumbled early can’t count on fellow playoff contenders being in the same underwater boats.  They have to play serious catch-up with rivals whose yachts have begun to float away.  An “average” playoff team has a .564 April win percentage.  So a club with a 9 -15 April is trying to catch teams who’ve gone 14-10 or better.  If the 15-9 April teams plays at “only” .537 ROS and gets 88 wins, it takes a .580 ROS from the poor April starter to overcome that.  Playing at .580 + level ROS has been done by only 15% of all teams, which equates to being one of the top three teams in one’s league after May 1st.

Those 8 playoff teams who started sub-.400 averaged a .604 ROS win percentage.  Five of the eight were .580 + ROS and the lowest ROS win percentage was .572 which translates to 93 wins over a full season.    In addition, there were four teams with a .580+ ROS that missed the playoffs.   Despite being better ROS than their key divisional or wild card rivals those four teams (2004 Giants, 2005 Indians, 2011 Red Sox, 2012 Angels) lost out on the playoffs because of their inferior April records.

The other side is that very strong Aprils can provide a cushion to play at less than .550 ROS. There are even occasions where teams with less than a .520 ROS have made it in due to strong Aprils: 2016 Mets, 2015 Astros, 2014 A’s, 2006 Cardinals, and 2000 Yankees.  Ironically there are two World Series winners in that group (Cardinals and Yankees).   The Cardinals were particularly unusual as they were the only team to make the playoffs with a sub-.500 ROS record.

The lone .600 + ROS who missed the playoffs (2005 Indians) provide a classic example. They were the second best team in the AL after April, outplaying their division rival and subsequent World Series winner White Sox   84-55  to  82-56  ROS.   However, with the 17-7 April of the Sox, and Indians’ poor 9 -14 start, Sox gained a 7.5 game cushion.  The double whammy was that the Tribe’s poor April also cost them the wild card to Boston.   Had the Indians played even 12-13 instead of 9-14 they’d have ousted Boston.   Of course Cleveland’s 13-16 July didn’t help either, nor did going 1 -5 the last week of the season (including a 3 game sweep by the Sox) after the Indians had whittled the lead down to 1.5 games on Sept. 24.  But the April cushion built by the Sox allowed them to withstand an incredible Aug/Sept run by Cleveland and the Tribe was forced to play unbelievably well to stay in the hunt.   This all happened before the second wild card was introduced in 2012, and if it had applied back then Cleveland would have made it as that second wild card.   So has this second wild card now made it easier for April stumblers to recoup ?



Adding a second wild card team has changed the odds in some meaningful ways as the following illustrates.

% of all teams who win 92 + games and make the playoffs % of all teams who win 87 -91 games and make the playoffs % who win 82-86 and make the playoffs
2012 – 2017               100 %               83 %         8 %
2000 – 2011                 94 %               45 %           7 %


Clearly 87 – 91 wins has had twice the chances of making the playoffs than before. Before 2012 teams needed to be stoking the engine every month to get to 92 wins. However with the bar now lowered to 88 wins since 2012, this allows more margin for error. That margin can go two ways. It can benefit teams who stumble in April and need a lesser ROS to get in.  In fact for teams who started less than .450 and then made the playoffs prior to 2012, the average ROS was .604.  For the three teams that have done that since 2012, the average ROS is .574.   But the post-2011 lower win threshold can also help teams who come out strong in April who don’t have to tear it up in the last 5 months to get in.   So which has it helped most ?  Following is a breakdown of the percentage of playoff teams after 2012 who’ve played at given ROS levels comparing those who had .600 + Aprils v. below .600 Aprils.

  REST OF SEASON WIN %’s            
April Win % 0.625 0.605 0.591 0.581 0.575 0.569 0.556 0.549 0.537 0.529 0.519 0.509
600 + Aprils 0% 9% 22% 26% 39% 48% 61% 61% 78% 78% 87% 96%
Below 600 6% 17% 31% 54% 63% 74% 80% 86% 91% 94% 100% 100%


Those who started .600 or better had a much lower burden to meet ROS.   Only 26% of the 600+ April teams who made playoffs achieved .580 ROS where over half of the below .600 Aprils had to meet that burden.  While having a .600+ April is no assurance of making the playoffs, it virtually is if teams play at least decently thereafter.   Here is what has happened to the 34 teams with 600+ Aprils from 2012-2017.

.600+ Aprils # Tms 550 + ROS 520-550 ROS 500-520 ROS Under 500 ROS
In Playoffs 23    14        6       3          0
Missed PO’s 11      0        2       2          7


As can be seen, 600+ April and 520+ ROS has been a successful formula 20 of the 22 times. The only two to miss were 2013 Rangers (91 wins) and 2012 Bucs (90 wins), who also happened to be the only 2 of 42 teams who’ve won 90+ since 2012 and missed the postseason. Playing .520 is hardly a torrid pace as it equates to 84 wins over a full season.   Playing at .500- .520 ROS isn’t playoff caliber yet 3 teams still made it, all helped by .650+ Aprils (2016 Mets, 2015 Astros, 2014 A’s).   The 7 teams who collapsed to sub-.500 after hot Aprils clearly didn’t deserve to get in.

One final cut of the data can establish who has been helped more by adding 2 more wild cards – the April surgers or the April stragglers. .565 ball equates to 92 wins and .520 ball equates to 84 wins . Teams who play at .565 levels ROS should make the playoffs.  Teams between .520-.564 should contend.

April Start Teams # PO teams .565 ROS –Made PO .520-.564 ROS-Made PO .500 -.519 ROS- PO
.565 + April

.500 + ROS

42    33                20  -20     15 – 10      7 – 3
.500-.565 A

.500 + ROS

24    16                12 – 12     10 –   4      2 – 0
.449- April

.500+ ROS

25    11               11 – 10     11 – 1     3 – 0


This defines the task confronting a good team with a sub-.500 April. Every year on average there are 4 such teams who rebound with .500+ ROS at a typical year looks like. However, they have to find a way to better several of the 11 teams who’ve started .500 + in April and are still +.500 and there are only 10 playoff spots.   Their only remedy is to play .565 + ball ROS and for one team (2012 Angels) even that wasn’t enough due to a terrible 8 -15 April.     But the .565+ April starter has it easier as a .520-.564 ROS gives him a 2/3 shot of still making it where only one team of 11 who started below .500 (2016 Giants) was able to eek into playoffs with less than .565 ROS.    The April .565 starter still has a shot with a tepid .500 – .520 ROS, but those are all teams as noted before that were red-hot in April (.650+).

Due to the abundance of teams starting well or decently (in April 2018, 13 teams were .565+ and 19 were .500+) the poor starters simply have to be a lot better ROS than their rivals to shove their way through the crowd.   The second wild card has benefitted the good April starters moreso than the good teams with bad Aprils. Of course the same math could be applied to any month, good or bad, so to paraphrase the classic Passover question:  why is April so different from all other months ?


Despite the fact that April is only 15% of the overall season, when early-mid season personnel decisions are being made, April results can still have considerable impact.   April’s record can influence decisions such as: the patience a team has for a younger player with early season struggles or whether the team tries for a mid- May trade to replace an injured starter and/or considers promoting a top notch AAA player despite his arb clock issues.  When trading season starts in June, 35% – 40% of the team’s record at that point has been baked in by April’s wins and losses.  Even by the late July deadline, April still comprises 25% of the season.  If early results have affected fan attitudes and attendance, ownership may be either more or less willing to commit dollars to bigger name players at the deadline.  These factors may give April importance beyond its mathematical impact on the standings.   That teams tend to mirror their April win-loss %’s as the season progresses may be in part that April can create a sort of self-fulfilling prophesy.

The 2014 Cleveland Indians were 75-60 after April 30th, the Oakland A’s were 70-63 over the same time. Yet Oakland got the wild card by 3 games over Cleveland due to a 18-9 April v. the Indians 10-17.   Early season results were still impacting July decisions as the A’s were buyers and the Indians sellers.   To be sure, the A’s record worsened post-July and the Indians got better.  But without Jon Lester (2.35  ERA with A’s) and Jeff Samardzija (3.14) who knows how much worse it might have been for the A’s .  While ridding themselves of Justin Masterson may have helped the Indians and trading Cabrera didn’t hurt, how much better would they have been had they gotten an outfielder and starting pitcher in July instead of being sellers ?

Conversely, the 2016 White Sox benefited from a 17 -8 April despite a May tailspin which left them with a 29 -27 record on June 4th and only 2 games behind in the AL Central. They then traded a very talented younger prospect named Fernando Tatis Jr.  for James Shields.  Needless to say this is a trade that has not worked well short or long term.  Despite the fact that the Sox had 3 straight losing seasons prior to 2016,  management seemed to believe that April/early May represented the success they felt the team was capable of as opposed to the more recent reality of losing.  Successful Aprils can sometimes keep wishful thinking alive for too long.


Clearly April has proven to be a good proxy for the team’s chances going forward that season. But April records, also have to be viewed in context of all the evidence.  How much of a factor were injuries, over or under performances, or new offseason acquisitions?  Thoughts of dumping contracts and rebuilding, while too premature for May 1st, are still quite logical particularly for poorer prior year clubs who are off to bad starts.

For clubs in the playoff hunt, April can have real impact since 3-5 wins one way or another can be make/break. Since 2013 teams with 87-88 wins have made the playoffs in 10 of 11 cases where only 2 of 14 teams with 85-86 wins have. Clearly these margins apply to other months’ results too, but as noted before, a very good or bad April can affect team decisions in June and July.   Having some breathing room afforded by a 16-10 April instead of the catch-up pressure of a 10-16 start can play into the psychology as well.

Winning the division winner is far preferable to having to win a one-game playoff as a wild card and April provides a good checkup on division rivals. Both Boston and NY look like they will fight it out all year although Toronto can’t be ignored. In the Central, the Indians’ are in a strong position with their chief rival, the Twins, are 4.5 games back already and the rest of the Central bad teams who’ve started with bad Aprils.   Houston’s good start helps especially since all of their closest chasers (Mariners, Angels, A’s) were sub-.500 teams last year, but the Angels improved through offseason acquisitions.  In the NL East, even though the Nationals are 5 games back they’re chasing teams who were all sub-.500 last year (Mets, Braves, Phillies).  Where the Dodgers, who are 8 games back, are pursuing a D-Back team that won 93 last year.  Turner’s absence hurt in April but so did the lack of offense from the rest of the team which may continue particularly since Seager is lost for the year.    Plus the bullpen woes cannot be overlooked. So April’s 12-16 record cannot be easily dismissed as an aberration.  Nor can the historical evidence of diminished playoff odds (20-25% range) of good teams who’ve had the Dodgers’ kind of April.   We shall all see soon enough.

We hoped you liked reading How Much Does April Matter? by rmasearch!

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