Answer:
increase
Step-by-step explanation:
Reserve ratio is the percentage of deposits that is required of commercial banks to keep as reserves. The lower the ratio, the higher the increase in money supply 
For example, assume reserve ratio is initially 10% of deposits. It is later reduced to 5%. 1000 is deposited 
Increase in money supply = deposit / reserve ratio 
1000 / 0.1 = 10,000
1000 / 0.05 = 20,000
Money supply increased when reserve ratio was decreased