| 2000 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | ||
|---|---|---|---|---|---|---|---|---|---|---|
| Total Cooling System Stock (thousands) | 249.0 | 387.7 | 393.3 | 404.9 | 417.1 | 429.8 | 443.2 | 457.1 | 471.7 | |
System Stock by Type (thousands) | ||||||||||
| Room | 81.0 | 93.9 | 88.2 | 87.2 | 86.1 | 85.1 | 84.1 | 83.1 | 82.1 | |
| Central | 168.0 | 293.8 | 305.1 | 317.7 | 331.0 | 344.7 | 359.1 | 374.0 | 389.6 | |
Shares (%) | ||||||||||
| Room | 32.5 | 24.2 | 22.4 | 21.5 | 20.6 | 19.8 | 19.0 | 18.2 | 17.4 | |
| Central | 67.5 | 75.8 | 77.6 | 78.5 | 79.4 | 80.2 | 81.0 | 81.8 | 82.6 | |
New Unit Efficiencies | ||||||||||
| Room (EER)1 | 9.4 | 11.2 | 11.2 | 11.3 | 11.3 | 11.4 | 11.5 | 11.5 | 11.6 | |
| Central (SEER)2 | 10.3 | 13.3 | 13.4 | 13.5 | 13.5 | 13.6 | 13.7 | 13.7 | 13.8 | |
Stock Efficiencies | ||||||||||
| Room (EER)1 | 8.3 | 10.7 | 10.8 | 10.9 | 10.9 | 11.0 | 11.1 | 11.2 | 11.2 | |
| Central (SEER)2 | 9.6 | 11.8 | 12.0 | 12.2 | 12.4 | 12.7 | 12.9 | 13.1 | 13.3 | |
Unit Capacity Ratio (Btu/hour) | ||||||||||
| Room | 9,898 | 9,129 | 9,131 | 9,218 | 9,285 | 9,353 | 9,472 | 9,489 | 9,507 | |
| Central | 33,466 | 33,282 | 33,291 | 33,140 | 32,989 | 32,827 | 32,634 | 32,637 | 32,640 | |
Footnotes:
1) Energy Efficiency Ratio.2) Seasonal Energy Efficiency Ratio.