(1.) What is the calculated value of the 3-year TOTAL deseasonalized demand in Cell F42 of worksheet: SI and regression?

D G A B C E F Month Demand Yearly average Seasonal Index Average SI Deseasonalized Time period 1/1/2019 2210 0.803514619 2/1/2019 2353 0.8555067414 3/1/2019 2835 1.030752916 4/1/2019 2745 0.9980306014 5/1/2019 2350 0.8544159976 6/1/2019 3433 1.248174519 7/1/2019 2550 0.9271322527 8/1/2019 2250 0.81805787 9/1/2019 2263 0.8227844266 10/1/2019 2590 0.9416755037 10 11/1/2019 3428 Put yearly average in below ce 1.246356613 11 2750.416667 1.45359794 12 13 12/1/2019 3998 1/1/2020 2513 0.8427230047 13 15 2/1/2020 2344 0.7860496311 14 3/1/2020 2476 0.8303152247 15 4/1/2020 3055 1.024480215 16 18 5/1/2020 3535 1.185446009 17 19 6/1/2020 3365 1.12843729 18 20 7/1/2020 2426 0.8135479544 19 8/1/2020 2788 0.9349429913 20 9/1/2020 2806 0.9409792086 21 10/1/2020 3397 1.139168343 22 11/1/2020 4097 Put yearly average in below ce 1.373910127 23 12/1/2020 5097 2982 1.709255533 24 1/1/2021 2629 0.7052984574 25 2/1/2021 2831 0.759490275 26 3/1/2021 2882 0.7731723675 27 4/1/2021 3520 0.9443326626 28 5/1/2021 3620 0.9711602951 29 6/1/2021 3879 1.040643863 30 32 7/1/202: 2891 0.7755868545 31 8/1/2021 3293 0.883433937 32 9/1/2021 3394 0.9105298457 33 10/1/2021 4408 1.182562039 34 36 11/1/2021 5175 Put yearly average in below ce 1.38832998 35 12/1/2021 6208 3727.5 1.665459423 36