From the second link:
Nationwide, an estimated 83% of marketplace enrollees qualify for subsidies, ranging from 13% in the District of Columbia and 35% in Hawaii to 92% in Wyoming and 93% in Mississippi. (Members of Congress and some of their staff obtain coverage through the DC exchange and are not eligible for subsidies, which is why the percentage there is so much lower than in the rest of the country.)
The take-up rate of subsidies – that is, the percentage of those eligible who have actually enrolled – is 21% in the U.S. as a whole and ranges from 10% or less in a number of states to 32% or more in Washington, Connecticut, California, Rhode Island, and Vermont. In general, states that are running their own exchanges have higher take-up rates, though some have low take-up due to widely-reported difficulties with their enrollment systems.
Among those qualifying for subsidies, we estimate that the average subsidy is $2,890 per person, ranging from a low of $1,350 in the District of Columbia and $1,780 in Utah to a high of $4,370 in Mississippi and $4,980 in Wyoming. These amounts are highly related to the premium levels in areas within each state. Tax credits are calculated by subtracting the amount each person is expected to pay based on a percentage of their income (which does not vary by state) from the premium for the second-lowest-cost silver plan in their area. Where premiums are low, tax credits will tend to be low as well, though the subsidized individuals themselves will pay the same as people with equivalent income who live in areas with higher premiums. Similarly, average subsidies will tend to be higher in states with older enrollees since they face higher premiums.