Now the proportion of bears has more than doubled.

In the last five years, the proportion of vehicles under lease has doubled.

During the last two decades, the proportion of births to mothers over 35 has more than doubled.

The proportion of women in the top three grades has almost doubled in the past four years.

The proportion of such marriages doubled from 20% to 40% between 1989 and 2003.

The proportion of women among full-time faculty members doubled between 1972 and 1997, to 36 percent.

The proportion of families earning above $150,000 a year more than doubled between 1990 and 1997, from 4.5 percent to 11.6 percent.

By 1986, the proportion of communications contributions nearly doubled, Federal reports show.

The proportion of elderly living alone has almost doubled since the early 1970's, to 13 percent.

Let us assume that the proportion has doubled, even tripled, since then.