TABLE 2.

Average annual percent change for Medi-Cal enrollment, hydroxyurea prescriptions filled, and acute healthcare utilization

Age group in years	Average annual percent change pre-expansion (2011-2013)	Average annual percent change post-expansion (2014-2016)	Net Percent Change
Number of Medi-Cal enrolled participants
Cohort	0.6	−2.8	−3.4
≤11	4.1	−1.9	−6.0
12-21	0.0	−1.6	−1.6
22-34	0.8	−2.8	−3.6
35-64	−0.3	−3.7	−3.4
Percent of hydroxyurea prescriptions filled
Cohort	0.6	5.9	5.2
≤11	14.1	17.6	3.5
12-21	7.3	7.0	−0.3
22-34	−2.7	3.2	5.9
35-64	−3.3	1.8	5.2
Emergency department visit rate
Cohort	0.5	−1.1	−1.6
≤11	0.7	−5.6	−6.2
12-21	2.4	1.8	−0.6
22-34	1.0	−0.9	−1.9
35-64	−0.4	−0.9	−0.5
Hospital admission rate
Cohort	−1.2	−1.4	−0.2
≤11	−0.3	−0.1	0.2
12-21	3.1	2.5	−0.6
22-34	−0.2	−3.1	−2.9
35-64	−3.2	−1.3	1.9

Average annual percent change in Medi-Cal enrollment, hydroxyurea prescriptions filled, and acute health care utilization was calculated using the following equation:

$$\mathrm{Average}\mathrm{annual}\mathrm{percent}\mathrm{change}=⟦{\left(\frac{\mathrm{end}\mathrm{value}}{\mathrm{begining}\mathrm{value}}\right)}^{\frac{1}{\mathrm{change}\mathrm{in}\mathrm{years}}}-1⟧\times {100}^{}$$

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