In the month of May, Williams Company produced 5794 units of a product. The standard cost card indicates the following materials standard per unit of output: 1 kilogram @ $0.5 = $0.50. During May, 15450 kilograms of material were purchased at a total cost of $9374 and 6865 kilograms of materials were used. What is the material price variance for May? Note that a negative number indicates an unfavourable variance.