OK, since you did not give me the particular Correct Score selections, I will use an example for 0-0 and 1-1.
The indexes of 0-0 and 1-1 (their positions in the list of selections from top to bottom) are 1 and 6 respectively.
Therefore, their book% will be calculated using this formula:
100/football2_s_1_back_price + 100/football2_s_6_back_price
If you want to take into account the market commission, then the formula is slightly different:
100/((football2_s_1_back_price-1)*(1 – football2_commission/100) + 1) + 100/((football2_s_6_back_price-1)*(1 – football2_commission/100) + 1)