Working Moms - how long did you express for

Hi ladies

Just wanted to know how long the working moms used to express for (i.e. how many weeks or months) and on average how many feeds did you get out?

I pump twice at work (three when I can) and get two or three feeds out. Need to supplement with formula though as Hannah drinks 4 times during the day at creche and she has rice cereal for breakfast.