How efficient is the GaN charger at charging the iPhone?

Model	Rated Power	Rated Power to charge iPhone	Power Efficiency	Actual Power used to charge iPhone	Time to charge iPhone XS Max	Time to charge iPhone XR
HyperJuice 100W GaN charger	100W	18W	95%	17.1W	121 minutes	118 minutes
Anker Atome PD4	100W	18W	91%	16.38W	126 minutes	124 minutes
Apple 12W Charger	12W	12W	91%	10.92W	203 minutes	187 minutes