That site isn't close, at least on the Learjet 31A...
Fuel (GPH): 145.00
Fuel Costs/Gallon:1.79
Fuel Costs/Hour:259.71
Oil Costs per Hour: .50
Maintenance Cost/Hour:207.92
Hourly Engine Reserve:180.20
Prop T/R Reserve:11.88
Total Variable Costs/Hour:660.21
Average Speed (MPH):420.00
Cost/SM:1.57
Annual Insurance:15,000.00
Annual Hangar/Tiedown:17,821.78
Training:18,000.00
Total Fixed Costs:50,821.78
Hours/Year:224.75
Fixed Cost/Hour:226.15
Total Variable & Fixed Costs/Year:199,162.29
Total Costs/Hour:886.36
Total Cost/SM:2.11
For example, our insurance is 32K/yr. Training is more like 25K/yr. once you figure in travel/lodging expenses for at least 2 crewmembers. And they leave out some sort of important items like salary/benefits, maintenance tracking, charts, FMS Update subscriptions, etc...
About $250,000.00/yr. fixed cost plus about $1200/hr. DOC is more like it...