Table 2.

Weighting of unit values, green roof/wall ^†.

Study	Country Data	Uncertainty Measure	EUR-2010 Greenery Value	“Effect”, Unit Value (per m2)	Wg = 1/Vg
Peck et al. (1999) [34]	Canada, Toronto	interval	1,044	20.88	0.048
Hunt (2008) [40]	Canada, Toronto	interval	895	17.90	0.027
Gao & Asami (2007) [42]	Japan, Tokyo	SE of parameter	87	3.46	0.368
	Japan, Kitakyushu	SE of parameter	17	0.69	6.351
Ichihara et al. (2010) [43]	US, New York	SE of parameter	859	17.18	0.014
Des Rosiers et al. (2002) [41]	Canada, Québec	SE of parameter	189	3.78	0.281
Tomalty & Komorowski (2010) [44]	Canada, Toronto	none	3,174	63.47	0.001
	Canada, Toronto	none	1,111	22.22	0.008

^† 1/W_g yields V_g, the variance, and the square root of V_g yields the standard error estimate, SE_g. See further explanations in Table 1.