I have many years of data in simple monthly columns. I would like to look
at the same data in calendar quaters vs. months. i.e. the sum of Jan to Mar,
April to Jun, etc. and have it repeat for the entire column. Can I establish
a fomula that takes the sum of 3 rows of data in the column ( Jan+Feb+Mar)
then adds the next 3 rows( Apl+May+Jun) without including the previous
quarters numbers. Thanks in advance for your help.