Home-field advantage by year: A scary level of consistency for eight consecutive decades

If it feels like home-field advantage isn’t what it used to be, you’re right.

Or you’re completely wrong.

It depends on what your definition of “used to” is.

In looking at the 24,426 games on wyoming-football.com since 1894 where we know the winner, the loser and the location — and where the location was not a neutral site — we can see a consistent pattern in how often home teams win games. In total, home teams have 13,495 victories, 10,392 losses and 539 ties, a baseline winning percentage of .564. (If your math isn’t up to par, or if you’re just skimming, that means home teams have won 56.4 percent of Wyoming high school football games.)

Remember .564. It’s the measuring stick against which all other numbers in this post are measured.

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From season to season, home teams deviate subtly, but consistently, away from that baseline.

And those deviations are a factor of time — as long as that time is your great-grandpa’s time.

From 1920 to 1938, for 19 consecutive seasons, the home teams won Wyoming high school football games at above-average rates. Since 1939, though, winning percentages have been much more consistent.

Moreover, since 1939, there has been no consistent pattern. There have been stretches of home-field success and home-field struggle. In fact, since 1939, the winning percentage for Wyoming high school football teams is .557, which almost a full percent lower than our baseline.

For five straight years from 1942-46, home teams won at above-average rates, the longest such stretch in that era. However, in the 18 seasons from 1958-75, home teams won at an above-average rate just twice (1962 and 1968). That includes a seven-year stretch from 1969-75 where home teams won at below-average rates, the longest such streak.

That record was recently challenged; from 2013-18, the home team won at a below-average rate, too. In 2019 (.592) and 2020 (.577), the rate was above average, though; last year’s .563 was almost exactly on the average.

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The outliers stretch our expectations of what’s possible.

In 1977, home teams had a winning percentage of .483, the only time in Wyoming’s history that home teams finished below .500. Twice — in 1917 and again in 1984 — home teams went exactly .500, going 140-140 in 1984 and a much more modest 6-6-1 in 1917. The fourth-lowest winning percentage for home teams came recently, in 2015, when home teams had a winning percentage of .507.

Home teams did best in the early years. Since 1939, when numbers began evening out, home team’s best success came in 2002, when home teams had a winning percentage of .613. That was followed by 1989 (.612), 1983 (.612), 1991 (.611) and 2010 (.608).

Between 1921 — when high school football really took off in Wyoming — and 1939, the best home-field winning percentage came in 1923, when home teams went 62-27-4 (.688). In the 18 years between 1921 and 1938, home teams had a winning percentage of .622, almost 6 percent better than the average.

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So what happened? Why was home-field advantage so advantageous in the early years and less meaningful since 1939?

The short answer boils down, I think, to two factors: consistency and infrastructure.

In Wyoming’s early days of high school football, referees weren’t always the most neutral parties. The Wyoming High School Activities Association wasn’t even formed until 1931, 10 years after high school football got going. And even then, it took a while before the WHSAA coordinated officiating. Once officiating became more consistent, so did the game results.

As for infrastructure, take a look at this map of Wyoming in 1927. Count up the number of paved roads. Not many, are there? As the road system improved — as evidenced by this map from 1951, just 24 years later — teams could travel faster, spend less time on the road and arrive at games more refreshed and ready to play.

Since 1939, the most remarkable thing isn’t the change in home-field advantage. It’s the lack of it.

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Here’s a table listing the home-team records and winning percentages by year for Wyoming high school football:

Year	W	L	T	Home win %
2021	165	128	0	0.563
2020	173	127	0	0.577
2019	177	122	0	0.592
2018	153	138	0	0.526
2017	168	132	0	0.560
2016	163	134	0	0.549
2015	146	142	0	0.507
2014	156	141	0	0.525
2013	152	140	0	0.521
2012	168	127	0	0.569
2011	168	130	0	0.564
2010	174	112	0	0.608
2009	162	129	0	0.557
2008	162	123	0	0.568
2007	167	114	0	0.594
2006	161	136	0	0.542
2005	170	127	0	0.572
2004	169	123	0	0.579
2003	163	128	0	0.560
2002	174	110	0	0.613
2001	153	129	0	0.543
2000	138	122	0	0.531
1999	144	113	0	0.560
1998	146	109	0	0.573
1997	145	110	0	0.569
1996	141	108	0	0.566
1995	138	113	0	0.550
1994	140	108	0	0.565
1993	147	100	0	0.595
1992	139	112	0	0.554
1991	154	98	0	0.611
1990	143	127	0	0.530
1989	164	104	0	0.612
1988	149	125	0	0.544
1987	136	132	1	0.507
1986	149	113	0	0.569
1985	145	131	0	0.525
1984	140	140	0	0.500
1983	167	106	0	0.612
1982	146	124	0	0.541
1981	154	114	0	0.575
1980	141	122	0	0.536
1979	151	118	0	0.561
1978	161	107	0	0.601
1977	129	138	0	0.483
1976	157	117	1	0.573
1975	150	134	0	0.528
1974	153	132	11	0.535
1973	158	134	8	0.540
1972	158	129	10	0.549
1971	151	116	13	0.563
1970	145	132	10	0.523
1969	148	136	14	0.520
1968	167	125	4	0.571
1967	160	132	2	0.548
1966	153	127	2	0.546
1965	144	114	12	0.556
1964	146	114	12	0.559
1963	137	125	12	0.522
1962	154	112	5	0.577
1961	145	120	13	0.545
1960	138	133	13	0.509
1959	142	114	12	0.552
1958	136	109	10	0.553
1957	147	113	7	0.564
1956	137	100	9	0.575
1955	138	110	8	0.555
1954	133	97	12	0.574
1953	137	108	11	0.557
1952	131	99	12	0.566
1951	122	97	7	0.555
1950	130	100	4	0.564
1949	115	93	8	0.551
1948	110	87	7	0.556
1947	105	92	10	0.531
1946	102	63	19	0.606
1945	96	70	8	0.575
1944	104	66	7	0.607
1943	91	62	10	0.589
1942	78	52	10	0.593
1941	130	102	9	0.558
1940	109	100	7	0.521
1939	112	89	7	0.555
1938	101	65	16	0.599
1937	94	56	14	0.616
1936	100	51	15	0.648
1935	100	55	19	0.629
1934	93	60	10	0.601
1933	78	51	14	0.594
1932	82	50	11	0.612
1931	90	46	8	0.653
1930	88	47	11	0.640
1929	69	38	12	0.630
1928	61	43	13	0.577
1927	77	45	10	0.621
1926	68	41	9	0.614
1925	69	36	9	0.645
1924	64	36	8	0.630
1923	62	27	4	0.688
1922	53	31	2	0.628
1921	35	25	1	0.582
1920	17	6	3	0.712
1919	6	5	0	0.545
1918				No games
1917	6	6	1	0.500
1916	6	2	4	0.667
1915	9	7	0	0.563
1914	6	5	0	0.545
1913	6	2	1	0.722
1912	9	4	2	0.667
1911	7	2	1	0.750
1910	8	1	2	0.818
1909	7	5	1	0.577
1908	4	3	1	0.563
1894-1907	16	7	5	0.661
TOTAL	13495	10392	539	0.564

–patrick