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Two months ago, Russia’s statistics agency put a dent in its own credibility, publishing a growth estimate for 2018 that far exceeded even the most optimistic forecasts. Now it has a chance to explain itself.

While the initial report included only the full-year figure, data due to be published Monday will provide a quarterly breakdown, shedding some light on how the statistics agency reached the 2.3 percent result for the year, the highest since 2012. Most economists expect Russia to square the circle by publishing relatively strong data for the fourth quarter and revising up earlier estimates for the first nine months of the year.

The growth figure is just the latest positive surprise from an agency that went through a management shake-up after President Vladimir Putin and other officials criticized its data last year. But economists were shocked, noting the full-year figure was completely out of sync with data for the first three quarters of the year which showed growth averaging at around 1.5 percent -- roughly what many expect for this year, as well.

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“I’ll be very interested to see how much the data have been revised upwards,” said Iikka Korhonen, head of research at the Bank of Finland Institute for Economies in Transition. “We will have a more complete picture of the whole economy and the national accounts. That will help us in assessing how reliable the data is.”

More questions were raised about the quality of Russian data last month when Rosstat, as the statistics agency is known, said it would stop publishing monthly numbers that have shown a slump in disposable incomes for five straight years, shifting instead to quarterly ones.

Putin criticized the quality of the data at his annual press conference in December, raising concerns the Kremlin could be seeking to massage the numbers. Officials deny that. Economists say many of the recent surprises in the results reflect the imperfect information collected by the statistics agency, not political influence.

The Russian president was quick to tout the 2018 performance as evidence Russia is moving closer to his ambitious growth targets.

In the GDP figures, a key question is whether an apparent surge in construction last year contributed to the better-than-expected economic expansion. The statistics service said it revised up its growth data after it received delayed numbers from a Siberian region that’s home to Novatek PJSC’s $27-billion Yamal LNG project.

“The official explanation that construction in the North was reported once instead of being spread out across several years could be true,” said Anton Tabakh, the chief economist at Moscow-based credit assessor Expert Ra. “Most likely it is indeed a question of how it is being reflected in the records.”

Rosstat may revise its data to spread the effect of the construction boom evenly over the past two years, meaning that growth data going back to 2016 will have to be revised, the Bank of Russia’s research and forecasting department said in a report.

Russia’s economy grew 2.2 percent in the last three months of 2018, according to the median estimate of economists polled in a Bloomberg survey. That would be the fastest expansion since the third quarter of 2017, but was probably driven by a boost of economic activity before a value-added tax increase in January, so it’s unlikely to continue this year.

“Robust growth in 2018 was partly a mirage,” said Scott Johnson, a Russia economist at Bloomberg Economics in London. “The economy lost momentum in the second half of the year, and that weakness has carried over into 2019, with higher prices squeezing consumer demand.”

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