Changes in the technical and scale efficiency of rice production activities in the Mekong delta, Vietnam

Agricultural and Food Economics

Table 3 Summary of efficiency scores and percentage forms of returns to scale

Mean scores		1998	2002	2004	2006	2008	2010
Original technical efficiency (VRS)		0.534	0.547	0.631	0.699	0.677	0.650
Corrected technical efficiency (VRS)		0.484	0.497	0.593	0.667	0.645	0.606
Scale efficiency		0.925	0.895	0.927	0.935	0.942	0.902
Percentage	Constant returns to scale	1.2	1.2	1.3	1.1	2.7	0.9
	Increasing returns to scale	52.7	73.9	69.6	32.6	75.4	69.3
	Decreasing returns to scale	46.1	24.9	29.1	66.3	21.9	29.8

Source: Own calculations based on (GSO, General Statistics Office of Vietnam 1998, GSO, General Statistics Office of Vietnam 2002, GSO, General Statistics Office of Vietnam 2004, GSO, General Statistics Office of Vietnam 2006b, GSO, General Statistics Office of Vietnam 2008, GSO, General Statistics Office of Vietnam 2010).