PHOENIX — Arizona’s state government continues to collect more revenue than expected when lawmakers drafted the current budget last spring.

The latest monthly report by the Legislature’s budget staff says revenue through January totaled nearly $250 million more than forecast and that the monthly gain is due mostly to the individual income tax.

The report says January revenue collections totaled nearly $1.1 billion. That’s about 16 percent above the corresponding level in the prior fiscal year and $105 million more than the forecast for this fiscal year covering late 2017 and early 2018.

The budget staff says there are several possible explanations for the revenue surge.

Those include capital gains from the stock market’s growth in 2017 and increased profitability of “pass-through” businesses whose income is mostly paid through quarterly tax payments.