I have this information in which applicants for a conference are ranking their preferences for example (red, yellow, orange). What formula can I write so that I give the person their first choice, but then when that area gets filled up with more than 1/3 of the people at that conference it shows their second choice? I want it to be a first come, first serve kinda thing so that people are motivated to sign up earlier. Thank you so much to anyone that helps!