REDMOND — New estimates released by the Population Research Center at Portland State University place Redmond’s July 2007 population at 24,805, up 5.7 percent over the year before.

Redmond ranks as the 19th largest city in the state, moving ahead of West Linn within the last year. If the city’s growth continues, Redmond could surpass slower-growing Tualatin — population 26,025 — within the next year.

Despite the increase, Redmond’s growth has slowed in comparison to recent years. Between 2005 and 2006, the Portland State survey showed a 17.4 percent population increase, and between 2004 and 2005, the population climbed by 10.6 percent.

Portland State uses a variety of indicators to develop its population estimates, such as building permits, employment figures, school enrollments, voter registrations and utility bills. The state uses the university’s estimates to determine how to distribute a number of population-based sources of revenue, such as alcohol, tobacco and gasoline taxes.

Local governments keep a close eye on the numbers. For the city of Redmond and the Redmond School District, population growth is an important part of planning for future roads, parks, schools and more.

Doug Snyder, the chief operations officer for the school district, said population figures like those published by Portland State are useful, but only tell part of the story when it comes to projecting future school enrollment. The city covers a much smaller geographic area than the school district, and its growth doesn’t necessarily track with the growth of the student population.

Since the 1989-90 school year, the Redmond School District has grown from 4,124 students to 7,099 at the start of this year, an increase of about 72 percent.

By comparison, the city population has increased more than 300 percent since the 1990 census, when 7,125 residents were counted.

Snyder said the divergence between the two sets of figures suggests Redmond is getting older, with fewer and fewer households with school-age children.