Something odd is happening to the amount of money the Government collects to run the country.
Odder still is that authorities have been unable to provide a clear explanation regarding why taxes flowing into the State’s coffers are marginally less than expected.
The shortfall is not a cause for panic but it is important.
Ministers will shortly begin the process of preparing for the Budget.
That means officials will have to estimate how much money the State will have to spend next year and ministers will decide how much departments will have for public services or reducing taxes.
This week latest figures showed the State has collected 2.4% less in tax than it had expected so far this year.
There are a number of one-off factors which artificially depressed figures.
However, when these effects are stripped out some of the crucial taxes are down on expectations.
The most important category is income tax because it accounts for almost half of the tax collected each month.
So far this year it has fallen 3% or €200m short of the forecast for the first four months of the year.
Corporation tax is 27% behind, although is skewed by one off factors, and excise is 6% behind projections. But VAT has exceeded expectations by 6%.
The shortfall in income tax is perplexing because employment is rising quickly so one would expect an increase as more people get jobs.
"Income tax is made up of two components: Pay As You Earn (PAYE) and the Universal Social Charge (USC).
PAYE is rising as expected but USC has fallen behind.
The Department of Finance has asked that Revenue Commissioners to examine reasons behind the shortfall.
Dermot O’Leary, chief economist at Goodbody Stockbrokers, suggests that although the number of people in employment is rising, a larger percentage of those new positions may be lower paid jobs.
Last week there was interesting new information regarding the numbers on the minimum wage of €9.25 per hour. Data from the Central Statistics Office indicated 10% of workers surveyed in the Quarterly National Household Survey who reported their earnings were on the minimum wage.
While there are some concerns about the tax take the Department of Finance remains of the view that the State will achieve its tax forecasts for 2017.
However, if the current shortfall persists it means the amount of money for tax cuts and additional spending is likely to be curtailed in the next Budget.
Ireland is expected to be one of the fastest growing economies in Europe this year.
But those who hope that economic buoyancy will translate into reduced taxes or additional spending next year may be disappointed.