Budget Variance
  
Budget variances can be calculated by governments, corporations, individuals...pretty much anyone who operates (or tries to operate) on a budget.
The variance is the difference between the budgeted (or predicted) expense or revenue (income)...and the actual one.
So if you budgeted $50 for your phone bill, but then downloaded a bunch of apps and brought your bill up to $70, the variance would be the $20 over what your anticipated amount was.