How do you calculate RSFE and Sum of Abs. Deviation ??

Month	Actual Demand	Forecasted Demand	Deviation	RSFE	Absolute Deviation	Sum of Abs. Deviation	MAD	TS
1	950	1,000	-50	-50	50	50	50	-1
2	1,070	1,000	+70	+20	70	120	60	.33
3	1,100	1,000	+100	+120	100	220	73.33	1.64
4	960	1,000	-40	+80	40	260	65	1.2
5	1,090	1,000	+90	+170	90	350	70	2.4
6	1,050	1,000	+50	+220	50	400	66.67	3.3