To convert percent effort to person months, multiply the percentage of your effort associated with the project times the number of months of your appointment. For example:
25% of a 9 month academic year appointment equals 2.25 (AY) person months (9 x 0.25= 2.25)
10% of a 12 month calendar appointment equals 1.2 (CY) person months (12 x 0.10 = 1.2)
35% of a 3 month summer term appointment equals 1.05 (SM) person months (3 x 0.35= 1.05)
10% of a 0.5 FTE 12 month appointment equals 0.6 (CY) person months (12 x .5 X .1 = 0.6)
If the regular pay schedule of an institution is a 9 month academic year and the PI will devote 9 months at 30% time/effort and 3 months summer term at 30% time/effort to the project, then 2.7 academic months and .9 summer months should be listed in the academic and summer term blocks of the application (9 x 30% = 2.7 person months; 3 x 30%= .9)
Keep in mind that you can include up to two decimal places to report partial months in the SF424 (R&R) budget for competing applications. However, person months reported in the Research Performance Progress Report (RPPR) should be reported in whole numbers (1-12), rounded to the nearest whole person month; e.g., 1.6 person months would be entered as 2 person months.
For more information, visit our frequently asked question page on usage of person months.