https://www.bls.gov/cex/2015/combined/cucomp.pdf
For a family with school age kids, average income is 110,541.
And LZ overestimated many expenses, for example
Federal income tax is $13,096, not $14,000
average state tax is $3,905, not $6,000
average health insurance is $3,702, not $6,000
average rent/mortgage is $1,277 per month, not $1,800 per month
Total difference in above items is $22,234