finding a 60 min peak

Hi all,

this is my first post and i am still a novice to excels wonderful capabilities.. so please bear with me and keep in mind that i am trying to learn it

i have a massive list (a lot of colums and rows over 90000 )- with a colum for a timestamp and a colum with values for this timestamps.

i need to find the highest sums for those values for several rows. i am looking for the top 30-50 sums ------ in a 60-minute period.

so i need to see the start and end timestamp of the 60 minute period, the sum of the value inside this period. teh 60 minute period is not following the hours 9-10 but rather 9:23 - 10:23 if thats the timeframe where i have the highest sum of the values?

i hope my question is clear..

thx for your help