A History of Home Advantage
Home advantage is a much studied topic, and many people have offered suggestions as to where it originates: the motivational effect of playing in front of your own fans, the comfort of a familiar environment and match day routine, the possible influence of home fans on the referee (something that I want to come back to in a later post), the wearying effect of away team travel, or simply a higher expectation of home team success. It is present in many sports (see here), in many countries (see here).
In future posts I’d like to take a more detailed look at some of the factors that might contribute to the home advantage effect, but first let’s start with some basic statistics: how big is the home advantage, how does it compare across the top four divisions in England, and how has it varied since the birth of organised football?
Home Advantage 101
The table below shows the percentage of games won by the home team, away team and drawn in the last 21 years of the top four divisions of English football.
|Table 1: Home win, away win and draw percentage of games played in England’s top four divisions since the 1996/97 season. Percentages may not exactly sum to 100 because of rounding.|
The headline message is that across all games played in the English professional leagues in the last few decades, the home team wins 44%, the away team 28% and 27% are drawn. If home advantage didn’t exist, home and away teams would win the same proportion of games.
Table 1 also shows that home advantage declines slightly as we move down the leagues. On average, home teams in the EPL are 70% more likely to win than the game than the away team; this falls to 50% in League 2. There may be reasons for this but they are not immediately apparent.
The decline of home advantage
Figures 1 to 3 below show the home, away and draw win fractions in the top four divisions of English football in each year of their existence since 1888, with each coloured circle representing one of the divisions. The gray line shows a smoothed average across all four divisions.
The results are intriguing. Figure 1 demonstrates that the percentage of home wins in English football has certainly decreased over the last 120 years, particularly in the post-war era where there has been a steady decline.
What’s driving this? Figures 2 and 3 show the underlying dynamics are complex.
In the first twenty years of the Football League the home win percentage fell from around 60% to the mid-fifties, compensated by an increase in draws. Then, for the fifty years to 1960, the away win and draw percentage hovered around the low 20s, increasingly slightly. However, in the 1960’s, the draw percentage suddenly jumped up to its current level and have flat-lined since. Since the late 70’s, the rate of away victories has steadily increased to around 30%.
It seems reasonable that the increasing away win percentage may initially have been a result of the rule change in 1981 awarding three points for a win rather than two: teams playing away from home had more motivation to go for a win. But then why has the draw percentage not decreased appreciably, and why has the away percentage continued to steadily rise since?
Some have pointed to the increasing impact of television, suggesting that away team players – knowing their fans can now monitor their performance – try harder. But most televised games are in the top division, so why do we see similar trends in the lower divisions? Importantly, it’s clear that whatever the factors are that drive these changes, they are present in all four divisions.
The increasing professionalization of the sport, including improved training methods, increased financial rewards and better, more consistent officiating has almost certainly played its part gradually eroded the natural advantage provided by playing on home turf.
Another interesting proposition is that home advantage derives from a territorial urge to repel interlopers; as a motivational factor, it is reasonable to think that this would be felt most keenly by players who are from the same area as team they are playing for. Could it be then, that as teams were increasingly built through buying and selling players rather than through developing home grown talent, the inbuilt motivational factor of playing at home has gradually been weakened? This would be a very interesting theory to test further.
|Figure 1: Percentage of home wins in the English top four divisions. The grey line shows a smoothed average over all divisions.|
|Figure 2: Percentage of away wins in the English top four divisions. The grey line shows a smoothed average over all divisions.|
|Figure 3: Percentage of draws in the English top four divisions. The grey line shows a smoothed average over all divisions.|