Oslo Company prepared the following contribution format income statement based on a sales volume of $1,000$ units $($the relevant range of production is $500$ units to $1,500$ units$)$:

Sales $ $22,100$

Variable expenses $12,700$

Contribution margin $9,400$

Fixed expenses $7,708$

Net operating income $ $1,692$

Required:

If sales increased to $1,001$ units, what would be the increase in net operating income?