This table gives the value of z for which 
P(x > z) equals the given probability p.
Also, the value of p that is 1 sd lower.
Probabilities given in percent.

 p   z  p(z-1)    p   z  p(z-1)
--------------   --------------
 1  2.33   9     26  0.64  64
 2  2.05  15     27  0.61  65
 3  1.88  19     28  0.58  66
 4  1.75  23     29  0.55  67
 5  1.64  26     30  0.52  68
 6  1.55  29     31  0.50  69
 7  1.48  32     32  0.47  70
 8  1.41  34     33  0.44  71
 9  1.34  37     34  0.41  72
10  1.28  39     35  0.39  73
11  1.23  41     36  0.36  74
12  1.17  43     37  0.33  75
13  1.13  45     38  0.31  76
14  1.08  47     39  0.28  76
15  1.04  49     40  0.25  77
16  0.99  50     41  0.23  78
17  0.95  52     42  0.20  79
18  0.92  53     43  0.18  79
19  0.88  55     44  0.15  80
20  0.84  56     45  0.13  81
21  0.81  58     46  0.10  82
22  0.77  59     47  0.08  83
23  0.74  60     48  0.05  83
24  0.71  62     49  0.03  84
25  0.67  63     50  0.00  84