The following data for a pottery company pertain to the production of 2,000 clay pots during July.

Direct Materials (all materials purchased were used):

Standard cost: $2.00 per kilogram of clay

Total actual cost: $10,640

Standard cost allowed for units produced was $12,000

Materials quantity variance was $800 favourable

Direct Manufacturing Labour:

Standard cost is 2 pots per hour at $24.00 per hour

Actual cost per hour was $24.50

Actual labour was 1028 hours

What is the materials price variance?