less than $10,000
3.28
$10,000 to $19,999
2.91
$20,000 to $29,999
2.83
$30,000 to $39,999
2.67
$40,000 to $49,999
2.71
$50,000 to $59,999
2.45
$60,000 to $69,999
2.33
$70,000 to $79,999
2.56
$80,000 to $89,999
2.64
$90,000 to $99,999
2.33
more than $100,000
2.28
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