al value. This technique has the nice advantage of providing a reasonable disguise 
for the numeric data while still keeping the range and distribution of values in the 
column within viable limits. For example, a column of sales data might have a 
random variance of 10% placed on it. Some values would be higher, some lower but 
all would be not too far from their original range. 
 
Verdict: The number variance technique is occasionally useful and can prevent 
attempts to correlate true records using known 