Top budget officials in the Patrick administration and the Massachusetts House and Senate have agreed on a single estimate for how much the state is expected to collect in revenue in the fiscal year beginning July 1.  That estimate is $24.3 billion.  Of that, nearly $1.2 billion is expected to come from taxes on capital gains. About 10 percent _ or $122 million _ of those capital gains dollars would automatically be deposited in the state's rainy day savings fund.