ENERGY STAR Most Efficient 2018 — Furnaces

ENERGY STAR Most Efficient in 2018The ENERGY STAR Most Efficient 2018 designation recognizes the most efficient products among those that are ENERGY STAR certified. These exceptional furnaces represent the leading edge in energy efficient products this year. Access the full list of products recognized as ENERGY STAR Most Efficient in Excel.

AirEase A97USMV Series with Comfort Sync Communicating Thermostat

Features:

The AirEase - Pro Series A97mv furnace advance engineering delivers year round performance, with utility saving you’ll see very month. Featuring a modulating heating system with a variable-speed fan, the A97mv with Comfort Sync® efficiently adjusts heating output as the external temperature changes throughout the day - insuring consistently precise temperature control throughout your home. The a97mv has an AFUE of up to 97%, meaning it coverts a full 97% of your fuel into usable heat. That means you can keep your home warm and cozy, while still remaining energy-efficient, all winter long.

Every piece of AirEase’s Pro Series equipment means control, precision and efficiency. Temperature. Humidity. Air quality. With the Pro Series, you’re in control of every aspect of your home’s climate, as well as your energy costs.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
A97USMV070B12S-* 66 97 64 299 $705 $12,683 21%
A97USMV090C12S-* 88 97 80.7 307 $881 $15,855 22%
A97USMV090C16S-* 88 97 79.4 389 $876 $15,770 21%
A97USMV090C20S-* 88 97 79.5 354 $873 $15,720 21%
A97USMV110C20S-* 110 97 95.5 409 $1,047 $18,852 21%
A97USMV135D20S-* 132 97 112.1 550 $1,237 $22,266 21%
A97DSMV070B12S-* 66 97 64.5 282 $708 $12,744 21%
A97DSMV090C16S-* 88 97 80.2 321 $877 $15,788 21%
A97DSMV090C20S-* 88 97 80.3 340 $880 $15,844 21%
A97DSMV110C20S-* 107 97 95.1 380 $1,040 $18,719 21%
Airquest<sup>®</sup> VC 97 Series with Observer™ Control

Airquest® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Airquest® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the furnace to operate on a quieter low-fire setting unless thermostat calls for more fire.

Airquest® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
Arcoaire<sup>®</sup> VC 97 Series with Observer™ Control

Arcoaire® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Arcoaire® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the Arcoaire® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire. Arcoaire® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
F9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
F9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
F9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
F9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
F9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
F9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%

Armstrong Air A97USMV Series with Comfort Sync Communicating Thermostat

Features:

The Armstrong Air - Pro Series A97mv furnace advance engineering delivers year round performance, with utility saving you’ll see very month. Featuring a modulating heating system with a variable-speed fan, the A97mv with Comfort Sync® efficiently adjusts heating output as the external temperature changes throughout the day - insuring consistently precise temperature control throughout your home. The a97mv has an AFUE of up to 97%, meaning it coverts a full 97% of your fuel into usable heat. That means you can keep your home warm and cozy, while still remaining energy-efficient, all winter long.

Every piece of Armstrong Air’s Pro Series equipment means control, precision and efficiency. Temperature. Humidity. Air quality. With the Pro Series, you’re in control of every aspect of your home’s climate, as well as your energy costs.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
A97USMV070B12S-* 66 97 64 299 $705 $12,683 21%
A97USMV090C12S-* 88 97 80.7 307 $881 $15,855 22%
A97USMV090C16S-* 88 97 79.4 389 $876 $15,770 21%
A97USMV090C20S-* 88 97 79.5 354 $873 $15,720 21%
A97USMV110C20S-* 110 97 95.5 409 $1,047 $18,852 21%
A97USMV135D20S-* 132 97 112.1 550 $1,237 $22,266 21%
A97DSMV070B12S-* 66 97 64.5 282 $708 $12,744 21%
A97DSMV090C16S-* 88 97 80.2 321 $877 $15,788 21%
A97DSMV090C20S-* 88 97 80.3 340 $880 $15,844 21%
A97DSMV110C20S-* 107 97 95.1 380 $1,040 $18,719 21%
Bryant 987M Evolution<sup>®</sup> System Series with Evolution Control

Bryant 987M Evolution® System Series with Evolution Control

Features:
The Evolution® System 987M furnace has a new modulating gas valve that matches heating output to the home's heating needs to provide precise heating power for maximum comfort. True multi-position design allows upflow, downflow or horizontal installation with up to 98.3% AFUE performance in all configurations.

Evolution® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
987MA42060V17A 60 97.4 46.7 154 $507 $9,128 22%
987MA42080V17A 61 98.5 62.1 410 $697 $12,541 21%
987MA60060V21 80 97.4 77.4 458 $863 $15,527 20%
987MA60080V21 80 97.2 79 410 $874 $15,735 21%
987MA66100V21 100 97.3 94.8 438 $1,043 $18,777 21%
987MA66120V24A 120 97.2 109 505 $1,200 $21,592 21%
Carrier 59MN7 Infinity<sup>®</sup> 98 Series with Infinity<sup>®</sup> Control

Carrier 59MN7 Infinity® 98 Series with Infinity® Control

Features:
59MN7 Infinity® 98 Furnace with Greenspeed™ Intelligence achieves AFUE of up to 98.5%. Greenspeed™ intelligence adjusts modulating gas valve output from 40% to 100% of capacity in one-percentage-point increments for precise comfort. Variable-speed ECM blower and inducer motors operate at quieter, lower speeds.

Infinity® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
59MN7A060V17--14 60 97.4 46.7 154 $507 $9,128 22%
59MN7A060V21--20 61 98.5 62.1 410 $697 $12,541 21%
59MN7A080V17--14 80 97.4 77.4 458 $863 $15,527 20%
59MN7A080V21--20 80 97.2 79 410 $874 $15,735 21%
59MN7A100V21--22 100 97.3 94.8 438 $1,043 $18,777 21%
59MN7A120V24--22 120 97.2 109 505 $1,200 $21,592 21%
Day & Night ConstantComfort<sup>®</sup> VC 97 Series with Observer™ Control

Day & Night ConstantComfort® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Constant Comfort® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the furnace to operate on a quieter low-fire setting unless thermostat calls for more fire. Day & Night® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
ComfortMaker SoftSound<sup>®</sup> VC 97 Series with Observer™ Control

ComfortMaker SoftSound® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, SoftSound® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the furnace to operate on a quieter low-fire setting unless thermostat calls for more fire. ComfortMaker® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
Heil Quietcomfort<sup>®</sup> VC 97 Series with Observer™ Control

Heil Quietcomfort® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, QuietComfort® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the furnace to operate on a quieter low-fire setting unless thermostat calls for more fire. Heil® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
ICP Commercial<sup>®</sup> VC 97 Series with Observer™ Control

ICP Commercial® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, ICP Commercial® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the ICP Commercial® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire.

ICP Commercial® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
F9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
F9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
F9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
F9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
F9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
F9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
ICP Commercial<sup>®</sup> VC 97 Series with Observer™ Control

ICP Commercial® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, ICP Commercial® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the ICP Commercial® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire.

ICP Commercial® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
Keeprite<sup>®</sup> VC 97 Series with Observer™ Control

Keeprite® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Keeprite® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the furnace to operate on a quieter low-fire setting unless thermostat calls for more fire. Keeprite® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
Kenmore<sup>®</sup> VC 97 Series with Observer™ Control

Kenmore® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Kenmore® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the Kenmore® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire.

Kenmore® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
F9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
F9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
F9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
F9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
F9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
F9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%
Kenmore<sup>®</sup> VC 97 Series with Observer™ Control

Kenmore® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, Kenmore® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the Kenmore® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire.

Kenmore® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
G9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
G9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
G9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
G9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
G9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
G9MAE0601714A 120 97 109.2 506 $1,202 $21,632 21%
Lennox SLP98V Series with iComfort Wi-Fi<sup>®</sup> Control

Lennox SLP98V Series with iComfort Wi-Fi® Control

Features:
The Dave Lennox Signature SLP98V gas furnace features efficiencies up to 98.7% AFUE. Modulating gas heat and variable speed blower provide precise comfort, quiet operating sounds, and high energy savings. Fully communicating controls offer advanced diagnostics to exchange system information and to ensure optimal performance and efficiency.

To view compatible central air conditioners and air-source heat pumps models, see the ENERGY STAR Most Efficient CAC-ASHPs page.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
SLP98DF070XV36B -* 66 97.5 64.2 329 $710 $12,779 21%
SLP98DF090XV36C -* 88 97.5 80.4 348 $882 $15,878 22%
SLP98DF090XV48C -* 88 97.5 79.8 402 $882 $15,871 21%
SLP98DF090XV60C -* 88 97.5 79.9 374 $880 $15,835 21%
SLP98DF110XV60C -* 110 98.2 94.0 509 $1,042 $18,765 21%
SLP98UH070XV36B -* 66 97.4 64.1 361 $712 $12,823 21%
SLP98UH090XV36C -* 88 98 79.7 387 $879 $15,823 22%
SLP98UH090XV48C -* 88 97.5 79.0 494 $883 $15,900 20%
SLP98UH090XV60C -* 88 98.7 78.8 349 $865 $15,578 23%
SLP98UH110XV60C -* 110 97.5 95.0 465 $1,048 $18,867 21%
SLP98UH135XV60D -* 132 97.5 128.6 671 $1,423 $25,622 21%

Rheem Prestige R97V Series with EcoNet Control Center

Features: Prestige® R97V furnaces feature a modulating gas valve from 40% to 100% of capacity and variable speed blower provide the ultimate in comfort, quiet operation and energy savings. Fully communicating EcoNet control provides advanced diagnostics and system information to ensure optimal performance and efficiency.

EcoNet® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
R97VA060M317USA 56 97 47.3 234 $522 $9,399 21%
R97VA070M317USA 70 97 62.5 341 $693 $12,482 20%
R97VA085M521USA 84 97 77.9 442 $866 $15,590 20%
R97VA100M521USA 98 97 92.9 578 $1,038 $18,692 20%
R97VA115M524USA 112 97 103.9 673 $1,164 $20,958 20%

Rheem Prestige R98V Series with EcoNet Control Center

Features: Prestige® R98V furnaces feature a modulating gas valve from 40% to 100% of capacity and variable speed blower to provide the ultimate in comfort, quiet operation and energy savings. Fully communicating EcoNet control provides advanced diagnostics and system information to ensure optimal performance and efficiency.

EcoNet® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
R98VA060M317USA 56 98.7 47 255 $521 $9,383 22%
R98VA070M317USA 70 98.3 62.5 312 $690 $12,425 22%
R98VA085M521USA 84 98.1 77.8 447 $866 $15,581 21%
R98VA100M521USA 98 98.1 92.4 522 $1,027 $18,488 21%
R98VA115M524USA 112 98.6 93 559 $1,037 $18,674 21%

Ruud Ultra R97V Series with EcoNet Control Center

Features: Ultra® U97V furnaces feature a modulating gas valve from 40% to 100% of capacity and variable speed blower provide the ultimate in comfort, quiet operation and energy savings. Fully communicating EcoNet control provides advanced diagnostics and system information to ensure optimal performance and efficiency.

EcoNet® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
U97VA060M317USA 56 97 47.3 234 $522 $9,399 21%
U97VA070M317USA 70 97 62.5 341 $693 $12,482 20%
U97VA085M521USA 84 97 77.9 442 $866 $15,590 20%
U97VA100M521USA 98 97 92.9 578 $1,038 $18,692 20%
U97VA115M524USA 112 97 103.9 673 $1,164 $20,958 20%

Ruud Ultra U98V Series with EcoNet Control Center

Features: Ultra® U98V furnaces feature a modulating gas valve from 40% to 100% of capacity and variable speed blower to provide the ultimate in comfort, quiet operation and energy savings. Fully communicating EcoNet control provides advanced diagnostics and system information to ensure optimal performance and efficiency.

EcoNet® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
U98VA060M317USA 56 98.7 47 255 $521 $9,383 22%
U98VA070M317USA 70 98.3 62.5 312 $690 $12,425 22%
U98VA085M521USA 84 98.1 77.8 447 $866 $15,581 21%
U98VA100M521USA 98 98.1 92.4 522 $1,027 $18,488 21%
U98VA115M524USA 112 98.6 93 559 $1,037 $18,674 21%
Tempstar SmartComfort<sup>®</sup> VC 97 Series with Observer™ Control

Tempstar SmartComfort® VC 97 Series with Observer™ Control

Features:
Featuring self-configuring control, SmartComfort® VC 97 furnaces are built with stainless steel primary and secondary heat exchangers and achieve 97% AFUE. The modulating (multi-stage) gas valves allow the SmartComfort® VC 97 to operate on a quieter low-fire setting unless thermostat calls for more fire. Tempstar® control recommended for full functionality.
Model Number Capacity (MBtu/hr) Energy Use: Annual Gas Use (MMBtu) Annual Energy Use (kWh) Annual Cost (National Average)* Lifetime Cost to Operate** % Saving over Standard Furnace
AFUE
F9MAE0601714A 60 97 46.9 155 $509 $9,168 22%
F9MAE0602120A 61 98 62.4 412 $700 $12,602 20%
F9MAE0801714A 80 97 77.7 460 $866 $15,588 20%
F9MAE0802120A 80 97 79.1 411 $875 $15,756 21%
F9MAE1002122A 100 97 95.1 438 $1,046 $18,833 21%
F9MAE1202422A 120 97 109.2 506 $1,202 $21,632 21%

*Estimated using an average price of electricity of 10.9 cents per kilowatt hour. 
**Furnace lifetime is estimated at 18 years.