I have a set of daily data ranging from 1990-2010. Each day, a number of data points are recorded. The number of data points collected, however, are not consistent. For example, sometimes nine points are collected/ day; sometimes three points/day, sometimes one point/day, etc. I need to calculate a daily average for each day. Is there a way to program Excel to recognize the date change so that it will create an average for each day? Thanks in advance. An example of the data layout is below (in columns A, B and C):

Date Time Data
1-Jan-90 2:34 0.196
1-Jan-90 5:34 0.205
1-Jan-90 7:34 0.208
1-Jan-90 8:34 0.208
1-Jan-90 11:34 0.208
1-Jan-90 14:34 0.211
1-Jan-90 17:33 0.227
1-Jan-90 20:34 0.227
1-Jan-90 23:34 0.23
2-Jan-90 2:34 0.23
2-Jan-90 5:34 0.23
2-Jan-90 7:34 0.227
2-Jan-90 8:34 0.227
2-Jan-90 11:34 0.23
2-Jan-90 14:34 0.23
2-Jan-90 17:34 0.227
2-Jan-90 20:34 0.224
2-Jan-90 23:34 0.22
3-Jan-90 2:34 0.22
3-Jan-90 5:34 0.217
3-Jan-90 7:34 0.217
3-Jan-90 8:33 0.217
3-Jan-90 11:34 0.214
3-Jan-90 14:34 0.214
3-Jan-90 17:34 0.214
3-Jan-90 20:34 0.211
3-Jan-90 23:34 0.211