How was the "Cumulative % of SKU" column calculated?

Solved Problem 2(3of4)

Solved Problem 2 (3 of4) SKU 7 5 6 Description Signatures Cover stock Glue Boxes Inside Reinforcing tape Cardboard Used,'Year 150,000 10.000 75 20,000 3.000 18.000 Value SOA5 so.75 saooo S300 S005 $0.15 $002 Total Dollar usage S67,soo S7,500 S3.ooo Sl,soo S450 $81,310 pet ot Total 83.0% 3.7% 12% Cumulative % o' Dollar Value 830% 922% 959% 97.8% 990% 996% 1000% Cumulative % 143% 288% 420% sr.l% 714% 85.7% 1000% Class