You can 
put this solution on YOUR website! 
Hi
99% , 1%/2 = .5% and  invNorm(.005)= 2.58
	a	a/2	2-tailed crtical regions	
80%	0.2	10%	z <-1.28155	z >+1.28155
90%	0.1	5%	z <-1.645	z >+1.645
92%	0.08	4%	z <-1.751	z >+1.751
95%	0.05	2.50%	z <-1.96	z >+1.96
98%	0.02	1%	z <-2.326	z >+2.326
99%	0.01	0.5%	z<-2.576	z >+2.576