Not sure if this will help, but here are my attendence figures for this season. Last season my team finished 21-1 in d-3, and lost in first round of playoffs (didn't punt was trying to win just got beat) but was promoted due to record. Started this season with 18030 stadium and raised ticket prices after promotion.
week 1 record 0-0 atendence 18030 (sellout as would be expected)
week 2 , 0-2 , 16993
week 3 , 0-5 , 18030 (another sellout??)
week 4 , no home game that week
week 5 , 0-8 , 15345 (fans are giving up on season)
week 6 , 0-10 , 13334 (worst attendence but was first win)
week 7 , 1-11 , 18444 (1000 seats were added now 19030 capacity)
week 8 , 2-12 , 19016
week 9 , 3-13 , 18942
week 10 , 4-14 , 18830
week 11 , 5-14 , 19016
I don't think there was a big attendence problem unless it would be how fast the atendence fell off due to the record.