For whatever reason, bball-ref doesn't have league averages for advanced stats (I actually asked them about that and they said they'd consider doing it) so I took it upon the liberty to calculate it myself. Now, I used their league average page to estimate the totals based on games played during the different seasons so the figures aren't exact but I think they're at most off by .1% points, which is no big deal.

Anyways, thought this would be of interest to some people.

Code:
Season	 TS%	eFG%	Ast/FG	Unassisted
2010-11	 0.542	0.498	0.578	0.422
2009-10	 0.543	0.501	0.562	0.438
2008-09	 0.545	0.499	0.566	0.434
2007-08	 0.540	0.498	0.584	0.416
2006-07	 0.541	0.496	0.584	0.416
2005-06	 0.535	0.489	0.575	0.425
2004-05	 0.530	0.482	0.593	0.407
2003-04	 0.516	0.471	0.609	0.391
2002-03	 0.519	0.473	0.602	0.398
2001-02	 0.520	0.477	0.605	0.395
2000-01	 0.518	0.473	0.611	0.389
1999-00	 0.523	0.477	0.606	0.394
1998-99	 0.511	0.466	0.605	0.395
1997-98	 0.524	0.478	0.613	0.387
1996-97	 0.536	0.493	0.609	0.391
1995-96	 0.542	0.498	0.614	0.386
1994-95	 0.543	0.500	0.616	0.384
1993-94	 0.528	0.485	0.621	0.379
1992-93	 0.536	0.491	0.607	0.393
1991-92	 0.532	0.487	0.593	0.407
1990-91	 0.534	0.488	0.597	0.403
1989-90	 0.536	0.489	0.600	0.400
1988-89	 0.537	0.489	0.602	0.398
1987-88	 0.538	0.489	0.613	0.387
1986-87	 0.538	0.488	0.610	0.390
1985-86	 0.541	0.493	0.602	0.398
1984-85	 0.543	0.497	0.600	0.400
1983-84	 0.543	0.495	0.602	0.398
1982-83	 0.531	0.488	0.595	0.405
1981-82	 0.539	0.494	0.582	0.418
1980-81	 0.535	0.489	0.593	0.407
1979-80	 0.531	0.486	0.592	0.408
1978-79	 0.530	0.485	0.580	0.420
1977-78	 0.515	0.469	0.573	0.427
1976-77	 0.511	0.465	0.558	0.442
1975-76	 0.504	0.459	0.546	0.454
1974-75	 0.502	0.458	0.571	0.429
1973-74	 0.503	0.459	0.571	0.429
1972-73	 0.498	0.456	0.570	0.430
1971-72	 0.504	0.454	0.555	0.445
1970-71	 0.500	0.449	0.552	0.448
1969-70	 0.511	0.460	0.540	0.460
1968-69	 0.491	0.441	0.529	0.471
1967-68	 0.498	0.446	0.507	0.493
1966-67	 0.493	0.441	0.492	0.508
1965-66	 0.487	0.433	0.517	0.483
1964-65	 0.479	0.426	0.494	0.506
1963-64	 0.485	0.433	0.499	0.501
1962-63	 0.493	0.441	0.509	0.491
1961-62	 0.479	0.426	0.521	0.479
1960-61	 0.469	0.415	0.533	0.467
1959-60	 0.463	0.409	0.508	0.492
1958-59	 0.457	0.395	0.485	0.515
1957-58	 0.449	0.383	0.503	0.497
1956-57	 0.449	0.379	0.526	0.474
1955-56	 0.458	0.386	0.688	0.312
1954-55	 0.455	0.385	0.709	0.291
1953-54	 0.442	0.373	0.722	0.278
1952-53	 0.445	0.370	0.737	0.263
1951-52	 0.439	0.366	0.740	0.260
1950-51	 0.428	0.356	0.705	0.295
1949-50	 0.410	0.339	0.695	0.305
1948-49	 0.390	0.327	0.641	0.359
1947-48	 0.337	0.283	0.257	0.743
1946-47	 0.327	0.279	0.266	0.734