I have the following data:

id       client number year-month revenue
2        748 2014-12  92.25
3        748 2015-01  84.00
4        748 2015-06 751.89
5        749 2015-07 913.35
6        749 2015-08 334.96
I want the output as

client number  2014-12 2014-01 2015-06 2015-07 2015-08
748              92.25    84.00  751.89  0      0
749                0       0      0      913.35  334.96 
I want to do this in R