Historical attendances

This season we are likely to average around 27400 at St Andrews.

We will pretty much complete the season selling out 42 games home and away.

This will be the highest average home gates in 48 years except for the our first 3 of 4 consecutive initial Premier league years.

02/03 28831
03/04 29078
04/05 28760

Anyway, my question is: What happened in 1977/78 season for out average attendance to fall from 28k to 23k? Trevor Francis scored 29 goals in 77/78 and we finished 11th in the top division?

71/72 32k
72/73 36k
73/74 33k
74/75 30k
75/76 28k
76/77 28k

77/78 23k