Upgrading from:

NumericalMath`ListIntegrate`

The functionality of NumericalMath`ListIntegrate` is now accessible by using the built-in Mathematica kernel functions Integrate and Interpolation.

This gives an approximation to the integral of the function that produced the list of data:

Version 5.2 << NumericalMath`ListIntegrate`;
data = Table[n^2, {n, 0, 7}];
ListIntegrate[data, 1]