Incentive groups
Communications groups	$30	$40	$50	Total
	%	%	%	%
	(SE)	(SE)	(SE)	(SE)
Email prompt	8.7%	10.3%	13.3%	10.8%
	(0.02)	(0.02)	(0.02)	(0.01)
Email prompt with sweepstakes offer	7.8%	12.5%	12.8%	11.1%
	(0.02)	(0.02)	(0.02)	(0.01)
IVR reminder call	5.7%	7.2%	6.0%	6.3%
	(0.02)	(0.02)	(0.02)	(0.01)
Live phone prompt	10.6%	14.7%	11.0%	12.1%
	(0.02)	(0.02)	(0.02)	(0.01)
Direct mail postcard	17.6%	21.8%	25.5%	21.7%
	(0.02)	(0.03)	(0.03)	(0.02)
All of the above	34.1%	34.4%	31.6%	33.4%
	(0.03)	(0.03)	(0.03)	(0.02)
Total	14.1%	16.8%	16.7%	15.9%
	(0.01)	(0.01)	(0.01)	(0.01)