Table 1 Number of people facing low, moderate, significant, and severe water scarcity during a given number of months per year, for the average year in the period 1996–2005.

Number of months per year (n)	Billions of people facing low, moderate, significant, and severe water scarcity during n months per year				Billions of people facing moderate or worse water scarcity during at least n months per year	Billions of people facing severe water scarcity during at least n months per year
Number of months per year (n)	Low water scarcity	Moderate water scarcity	Significant water scarcity	Severe water scarcity
0	0.54	4.98	5.22	2.07	6.04	6.04
1	0.12	0.81	0.66	0.31	4.26	3.97
2	0.12	0.19	0.13	0.37	3.95	3.66
3	0.35	0.05	0.03	0.37	3.55	3.28
4	0.33	0.01	0.001	0.59	3.15	2.91
5	0.30	0	0	0.55	2.56	2.32
6	0.33	0	0	0.27	2.09	1.78
7	0.47	0	0	0.21	1.76	1.50
8	0.59	0	0	0.29	1.46	1.30
9	0.40	0	0	0.30	1.13	1.01
10	0.40	0	0	0.12	0.78	0.71
11	0.30	0	0	0.09	0.66	0.59
12	1.78	0	0	0.50	0.54	0.50
Total	6.04	6.04	6.04	6.04