The chi-square test for trend
The chi-square test for trend tests whether there is a linear trend between row number and the fraction of subjects in the left column. It only makes sense when the rows are arranged in a natural order (such as by age, dose, or time), and are equally spaced.
The test is also called the Cochran-Armitage test for trend.
It is explained clearly, with equations and an example, on pages 261-265 Altman's book referenced below. You can find all but the first of these pages at Google Books.