UPDATE 1-Indonesia's Semen Gresik Q3 net profit up 15.4 pct

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JAKARTA Oct 23 (Reuters) - Indonesia's largest cement producer, PT Semen Gresik Tbk (SMGR.JK), saw a 15.37 percent rise in its third-quarter net profit, according to Reuters calculations, showing a mild slowdown after robust growth in previous quarters.

The state-owned firm's July-September net profit climbed to 660.32 billion rupiah ($66.73 million) from 572.36 billion rupiah reported in the same period a year ago, based on calculations from its published nine-month and first-half results.

Semen Gresik recorded a 16.54 percent increase in sales revenue to 3.10 trillion rupiah from 2.66 trillion rupiah in the same quarter a year ago.

Semen Gresik's sales in the July-September period fell 9.54 percent to 4.27 million tonnes sales from 4.72 million tonnes in the year-ago period.

In the past years, lower interest rates have boosted the construction of infrastructure and residential projects, as the central bank's key interest rate BIPG fell to 8 percent at the end of 2007 from a record high of 12.75 percent in late 2005 on easing inflation. However, the central bank has raised its key interest rate six times this year, bringing the rate to 9.50 percent, as annual inflation accelerated to a two-year high of 12.14 percent in September. Analysts have said the interest rate hikes and looming inflation could put a brake on consumption growth. ($1 = 9,895 rupiah) (Reporting by Harry Suhartono; Writing by Tyagita Silka; Editing by Sugita Katyal)