With all but about 50 votes counted in the 2011 Tucson election, we know now that turnout was about 31 percent.

That comes as a surprise to The Range, which was predicting record turnout based on the number of vote-by-mail ballots that were returned in the mail.

What we didn’t realize, when we were analyzing the numbers of the city’s Web site: The number of those vote-by-mail ballots that were returned included ballots that were returned because people had moved and were no longer at those addresses, which inflated the percentages.

OK, ignore the above. We’re revising our earlier crunching. That 31 percent turnout number is based on the idea that the number of registered voters in the city of Tucson is 274,706, which appears on the city's election summary report. But that number is clearly wrong; the city mailed out 211,267 ballots and not all of those were deliverable.

But let’s go by the 211,267 ballots that were mailed out. Given that 85,340 people voted, we’ve got turnout of just about 40 percent, which puts it in line with the usual turnout in a mayoral race in Tucson.

The voter turnout in Tuesday’s election was actually higher lower than 33.5 percent that turned out in 2009 and way lower than just about the same as the 41 percent that turned out in the mayoral election years of 2003 and 1999, when Republican Mayor Bob Walkup faced competitive Democratic opponents. (In 2007, when Walkup faced only Green Party candidate Dave Croteau because the Democrats didn’t field a candidate, turnout was a low 27 percent.)

When you consider sheer numbers, more people turned in Tuesday’s election than in any year since 1999.

This year, 85,340 people cast ballots. In 2009, 74,168 people voted; in 2003, 77,857 people voted; and in 1999, 86,180 people voted.

So part of the lower percentage of voters comes from an expanded voter base. This year, 211,267 274,706 people were eligible to cast ballots, compared to 221,316 in 2009. In 2003, the city was home to only 191,406 voters. In 1999, there were 209,128 registered voters.

Part of that fluctuation has to do with population growth; some of it has to do with how effectively Pima County Recorder F. Ann Rodriguez is clearing out the deadwood on the voter rolls.

Here’s what you can say initially about the effect of the city’s new vote-by-mail system: On a percentage basis citywide, it ended in the same lower participation than average in a competitive mayoral election. In sheer numbers, it was close to a record breaker.

Here’s what we still don’t know: How the vote-by-mail system affected turnout in individual wards. Those numbers haven’t been made available yet, but we’ll crunch ’em when we can.

FWIW: We've written in the past about why people don't turn out in city elections.