Table 5. Areas with significant yield variability changes.

Crop	% of harvested area in 2000
	Reference [6]		R12		I14
	IVa	DVb	IV	DV	IV	DV
Maize	13	33	15–25	34–40	9–15	37–48
Soybean	9	28	25–28	33–36	10–16	34–45
Rice	16	19	30–34	16–25	17–19	19–26
Wheat	22	21	23–25	27–28	16–19	18–30

^a Yield variability significantly increased.

^b Yield variability significantly decreased.