MOSCOW, Dec 28 (Reuters) - The Russian federal statistics service, Rosstat, will from early 2022 adjust its algorithm to calculate weekly inflation with the same method it uses to produce monthly data sets, Rosstat said on Tuesday. Inflation is the main area of responsibility for the Russian central bank, which has raised its key interest rates seven times this year but failed to rein in consumer inflation that is on track to exceed 8% in 2021, far above the 4% target. The central bank, which hopes inflation will slow towards the target in 2022, has focused more on monthly inflation reports from Rosstat, saying weekly figures are "noisy". The change announced on Tuesday will alter the algorithm for the weekly data set so that it matches the monthly set. The bank is expected to raise rates again in the first quarter of 2022, a Reuters monthly poll of market experts showed last week. read more