In this paper assumptions had to be made regarding several issues. In this section we will
discuss the sensitivity of the results to changes in the most important ones. In our opinion
these are the assumptions on direct and indirect land use, on (regarding indirect land use) the
percentage of the area that would be built-on should restrictions on land use be removed and
on land prices. For each of these assumptions we will have to answer two questions. First,
how large is the uncertainty on the values that were assumed, and second, how sensitive are
the results to changes in these values (expressed, when possible, in percentage change of the
results as a result of a one-percent change in the assumed values)