State tax filing

My question is not if I should report my state tax refund, it is what value I should report on my federal return. My 1099-G from Colorado contains an amount of $1353 in box 2. This is $136 less than what my actual state refund of $1489 was last year.  The difference is due to a "Modified AGI Tiers for State Sales Tax Refund".  Which amount do I enter on my Federal return $1353 from the 1099-G or $1489 from last years tax form?

Thanks,

Ross