Haley Photocopying purchases paper from an out$-$of$-$state vendor. Average weekly demand for paper is $120$ cartons per week for which Haley pays $$30$ per carton. Inbound shipments from the vendor average $900$ cartons with an average lead time of $3$ weeks. Haley operates $52$ weeks per year; it carries a $4-$week supply of inventory as safety stock and no anticipation inventory. The vendor has recently announced that they will be building a facility near Haley Photocopying that will reduce lead time to one week. Further, they will be able to reduce shipments to $150$ cartons. Haley believes that they will be able to reduce safety stock to a $1-$week supply. What impact will these changes make to Haley's average inventory level and its average aggregate inventory value?

The changes decrease Haley's average aggregate inventory level by cartons. $($Enter your response as a whole number.$)$