IF ( BF_SAT_SS__c >= 1550, 34, 0) +
IF (AND( BF_SAT_SS__c >= 1510, BF_SAT_SS__c < 1550), 33, 0) +
IF (AND( BF_SAT_SS__c >= 1480, BF_SAT_SS__c < 1510), 32, 0) +
IF (AND( BF_SAT_SS__c >= 1440, BF_SAT_SS__c < 1480), 31, 0) +
IF (AND( BF_SAT_SS__c >= 1410, BF_SAT_SS__c < 1440), 30, 0) +
IF (AND( BF_SAT_SS__c >= 1370, BF_SAT_SS__c < 1410), 29, 0) +
IF (AND( BF_SAT_SS__c >= 1330, BF_SAT_SS__c < 1370), 28, 0) +
IF (AND( BF_SAT_SS__c >= 1300, BF_SAT_SS__c < 1330), 27, 0) +
IF (AND( BF_SAT_SS__c >= 1220, BF_SAT_SS__c < 1300), 26, 0) +
IF (AND( BF_SAT_SS__c >= 1180, BF_SAT_SS__c < 1220), 25, 0) +
IF (AND( BF_SAT_SS__c >= 1140, BF_SAT_SS__c < 1180), 24, 0) +
IF (AND( BF_SAT_SS__c >= 1110, BF_SAT_SS__c < 1140), 23, 0) +
IF (AND( BF_SAT_SS__c >= 1070, BF_SAT_SS__c < 1110), 22, 0) +
IF (AND( BF_SAT_SS__c >= 1030, BF_SAT_SS__c < 1070), 21, 0) +
IF (AND( BF_SAT_SS__c >= 990, BF_SAT_SS__c < 1030), 20, 0) +
IF (AND( BF_SAT_SS__c >= 950, BF_SAT_SS__c < 990), 19, 0) +
IF (AND( BF_SAT_SS__c >= 910, BF_SAT_SS__c < 950), 18, 0) +
IF (AND( BF_SAT_SS__c >= 870, BF_SAT_SS__c < 910), 17, 0) +
IF (AND( BF_SAT_SS__c >= 840, BF_SAT_SS__c < 870), 16, 0) +
IF (AND( BF_SAT_SS__c >= 800, BF_SAT_SS__c < 840), 15, 0) +
IF (AND( BF_SAT_SS__c >= 780, BF_SAT_SS__c < 800), 14, 0) +
IF (AND( BF_SAT_SS__c >= 750, BF_SAT_SS__c < 780), 13, 0) +
IF (AND( BF_SAT_SS__c >= 710, BF_SAT_SS__c < 750), 12, 0) +
IF (AND( BF_SAT_SS__c >= 680, BF_SAT_SS__c < 710), 11, 0) +
IF ( BF_SAT_SS__c < 680, 0, 0)
I'm not sure what you're trying to do by adding all of those closed IF scores, a field can only hold a single value. Could you try using a Nested IF like this?
IF ( BF_SAT_SS__c >= 1550, 34,
IF ( BF_SAT_SS__c >= 1510, 33,
IF ( BF_SAT_SS__c >= 1480, 32,
IF ( BF_SAT_SS__c >= 1440, 31,
IF ( BF_SAT_SS__c >= 1410, 30,
IF ( BF_SAT_SS__c >= 1370, 29,
IF ( BF_SAT_SS__c >= 1330, 28,
IF ( BF_SAT_SS__c >= 1300, 27,
IF ( BF_SAT_SS__c >= 1220, 26,
IF ( BF_SAT_SS__c >= 1180, 25,
IF ( BF_SAT_SS__c >= 1140, 24,
IF ( BF_SAT_SS__c >= 1110, 23,
IF ( BF_SAT_SS__c >= 1070, 22,
IF ( BF_SAT_SS__c >= 1030, 21,
IF ( BF_SAT_SS__c >= 990, 20,
IF ( BF_SAT_SS__c >= 950, 19,
IF ( BF_SAT_SS__c >= 910, 18,
IF ( BF_SAT_SS__c >= 870, 17,
IF ( BF_SAT_SS__c >= 840, 16,
IF ( BF_SAT_SS__c >= 800, 15,
IF ( BF_SAT_SS__c >= 780, 14,
IF ( BF_SAT_SS__c >= 750, 13,
IF ( BF_SAT_SS__c >= 710, 12,
IF ( BF_SAT_SS__c >= 680, 11,
0 ))))))))))))))))))))))))