to decrease /dɪˈkriːs/ /dɪˈkriːs/
to cut down /kʌt daʊn/ /kʌt daʊn/
to diminish /dɪˈmɪnɪʃ/ /dɪˈmɪnɪʃ/
to drop /drɑːp/ /drɒp/
to reduce /rɪˈduːs/ /rɪˈdjuːs/
to lessen /ˈlɛsən/ /ˈlɛsn/