(Adds crude, natural gas output, prices and well data)
MEXICO CITY, Feb 29 (Reuters) - Mexican state-run oil company Pemex on Monday said losses for the fourth quarter of last year widened to $9.8 billion, up nearly 44 percent from the year-earlier period, and marking its 13th consecutive quarterly loss.
The company's revenues for the quarter were $15.4 billion, down about 28 percent compared to the same period in 2014.
Pemex, whose market monopoly was ended by a sweeping energy reform in 2013, is in the midst of a round of cuts worth more than $5 billion brought on by a prolonged oil price rout and a decade-long production slump.
Like all oil companies, the Mexican oil giant is suffering a severe revenue crunch as crude prices have tumbled about 70 percent over the past year and a half.
The company said crude output for the quarter dipped 3.5 percent to 2.277 million barrels per day (bpd), weighed down by a 6 percent decline in heavy crude production.
Meanwhile, the average value of Mexico's oil exports fell by nearly half during the October to December period, from about $64 per barrel to $34 per barrel.
Natural gas production slid 6.8 percent for the quarter to total 5.369 billion cubic feet per day.
The company said that compared to the same period in 2014, its number of wells in operation during the quarter fell 3 percent, while completed wells were down 43 percent. ($1 = 18.0670 Mexican pesos) (Reporting by David Alire Garcia Editing by W Simon)