San Francisco 49ers : win % / playoff appearances per decade

The number of seasons with win % in the following ranges:
                                                    Decade
          Yrs.    80%+ 60-79% 40-59% 20-39% 0-19%    Ave.    Wins Losses
 2020s:     6      0      3      1      2      0     58.4      59    42     0
 2010s:    10      2      2      1      4      1     50.3      80    79     1
 2000s:    10      0      2      4      3      1     42.5      68    92     0
 1990s:    10      4      5      0      1      0     70.6     113    47     0
 1980s:    10      4      4      0      2      0     68.8     104    47     1
 1970s:    10      0      3      2      3      2     42.4      60    82     2
 1960s:     4      0      0      3      1      0     47.3      24    27     5
Totals:    60     10     19     11     16      4     54.9     508   416     9


Playoff appearances per decade

                Super  Yrs in
                 Bowl   Super Conf.  Conf.  In
          Yrs.   Wins   Bowl  Finals Semis  Playoffs
 2020s:     6      0      1      3      4      4
 2010s:    10      0      2      4      4      4
 2000s:    10      0      0      0      1      2
 1990s:    10      1      1      5      8      8
 1980s:    10      4      4      5      7      8
 1970s:    10      0      0      2      3      3
 1960s:     4      0      0      0      0      0
Totals:    60      5      8     19     27     29