Adsense words?

I read some where that this was the most expensive words for adsense. Not sure that that means. Somebody tell me how this makes you money by buying these words or using these words. I need some thoughts.

auto insurance 120,000 $38.49
cheap auto insurance 15,000 $34.80
car insurance 150,000 $32.46
cheap car insurance 18,000 $30.10
general auto insurance 230,000 $25.07
cheapest car insurance 10,000 $23.24
email marketing 18,000 $21.53
life insurance 100,000 $20.19
factoring 15,000 $19.72
online colleges 15,000 $19.53
online trading 10,000 $19.14
forex trading 44,000 $18.58
online degree 10,000 $18.12
online schools 10,000 $16.73
term life insurance 23,000 $16.58
online backup 10,000 $16.53
debt consolidation 66,000 $16.35
roth ira 35,000 $15.32
day trading 12,000 $14.85
life insurance quotes 10,000 $14.63
virtualization 10,000 $14.53
intervention 28,000 $13.45
network monitoring 10,000 $13.35
motorcycle insurance 23,000 $13.11
payday loans 82,000 $13.10
merchant account 15,000 $12.98
project management software 12,000 $12.77
home equity loan 15,000 $12.52
lemon law 18,000 $12.35
credit card offers 12,000 $12.24
home security systems 12,000 $11.78
debt relief 12,000 $11.73
debt consolidation loans 15,000 $11.72
debt solutions 10,000 $11.58
payroll 10,000 $11.50
student credit cards 12,000 $11.45
debt settlement 12,000 $11.41
credit counseling 15,000 $11.38
homeowners insurance 35,000 $11.04
security systems 18,000 $10.82
home security 18,000 $10.50
credit card processing 12,000 $10.34
call center 15,000 $10.27
mutual funds 35,000 $10.14
credit report 120,000 $10.03
refinance 18,000 $9.62
home loans 23,000 $9.60
small business loans 18,000 $9.37
reverse mortgage 28,000 $9.27