Russian retailer Magnit misses 2016 sales forecast

* 2016 sales rise 13 pct vs 14-16 pct guidance

* Annual sales growth slows to 7 pct in Dec (Shanghai: 600875.SS - news)

* Opened 927 convenience stores, fewer than planned (Adds context, details, updates share price)

MOSCOW, Jan 10 (Reuters) - Russia's biggest food retailer Magnit reported on Tuesday a 12.8 percent increase in 2016 sales, missing its 14-16 percent growth forecast.

The low-cost retailer has seen revenue growth slow as competition increased among stores seeking to tap into the pool of cash-strapped consumers who have cut back on spending as the rouble weakened and inflation ran high.

Analysts have said they expect Magnit to cede its leading position to X5 Retail Group in 2017 as the aggressively expanding competitor has been reporting sales growth in excess of 20 percent. Other retailers in the sector have yet to report their 2016 sales figures.

Magnit's 2016 sales rose to 1.1 trillion roubles ($18.3 billion) from 947.8 billion roubles in 2015, with growth slowing from the 24 percent achieved in 2015.

In December alone, sales growth slowed to 6.9 percent from more than 10 percent in previous months.

Like-for-like sales were down 0.3 percent last year as Magnit's customer numbers dropped 0.9 percent while the average bill rose 0.65 percent, Magnit said in a statement.

It also opened fewer new stores than planned, adding 927 convenience shops against an earlier forecast 1,000-1,100 stores, Magnit said in a statement.

Magnit Chief Executive Officer Sergey Galitskiy said in October the company was likely to end 2016 with fewer net openings than planned as it was ramping up closures of inefficient outlets.

Shares (Berlin: DI6.BE - news) in Magnit were down 3.3 percent by 0827 GMT in Moscow, underperforming a broader market index. ($1 = 59.9770 roubles) (Reporting by Maria Kiselyova; Editing by Christian Lowe)