Bowling Stat Help

Please help, I am looking for some help with a bowling stat sheet. See attached for problem.

Basically I want to be able to have my current formulas work even if the bowlers are not there a week.

Thanks

Could you just change IF(F5="","", to IF(F5="",I5, ?

That does work but I have 20 some weeks so it would always show the last average until it changes, which isn't terrible but I use that cell to make a graph of averages so it would show that you have an average for the whole year. My equation only showed the weeks they bowl and the next week.

Can there be a formula where it only does the average up to the next time they bowl?