Turkey's calendar-adjusted industrial production gained 7 percent in November 2017 compared to the same month in 2016, the Turkish Statistical Institute (TurkStat) announced Monday.

Industrial output is deemed a vital indicator for the economy as it is seen as a preliminary gauge for GDP growth.

Among three main sub-indexes, the manufacturing index rose the most with 7.1 percent during the same period.

In November, the annual increase in the electricity, gas, steam and air conditioning supply index was 6.7 percent while the mining and quarrying index was up 5.9 percent.

The term "calendar-adjusted" is used to refer to data without calendar and holiday-originated effects.

The seasonal- and calendar-adjusted production level was also up compared with the same figure for October 2017.

"Industrial production increased by 0.3 percent compared with the previous month," TurkStat said.

On a monthly basis, when the sub-sectors of the seasonally and calendar-adjusted industrial sector were examined, the mining and quarrying index rose 3.2 percent in November while the manufacturing index remained unchanged.

"Electricity, gas, steam and air conditioning supply index increased by 0.8% in November 2017, compared with the previous month," it added.

According to a survey conducted by Anadolu Agency's Finance Desk on Friday, a group of 15 economists estimated the calendar-adjusted industrial production index to increase by 5.9 percent year-on-year.