Maths problem: I don't know how to do, thanks.?

Last year:
Total expense = $5000
Renting a venue: $5000 × 60% = $3000
Buying souvenirs: $5000 - $3000 = $2000

This year:
Renting a venue: $3000 × (1 + 5%) = $3150
Buying souvenirs: $2000 × (1 - 1０%) = $1800
Total expense = $3150 + $1800 = $4950

Percentage change
= (4950 - 5000)/5000 × 1００%
= -1%