Bridget

The rate you have got is quite a bit higher than 'expectation'. The chances of two people in 23 sharing a birthday are just over 50%, far from a sure thing. Of course, for a sure thing you will need at least 367 people!

A simple (but tedious?) was to do a distribution 'curve' on Excel would be to simply have 365/366 rows and put a one against them for each person on that day. You could have a separate sheet for these 'tally marks' and then a consolidation sheet that shows, respectively, daily, weekly, monthly and quarterly totals. Then create graphs/charts to your heart's content...

cheer

the sunshine warrior