It shouldn't be the amount that you're worrying about but rather the quality of what is being written.
For me i wrote around 1600 words, i think? it's hard to remember lol, even though it was only last year. Ithink 1500 is a good amount and you should aim for around this in around 40 minutes.
I have literally practiced over and over again, handing in all my prac essays for marking. I get good marks but how ever much i cut down I can not fit within 40 min unless i cut stuff which is relevent. As soon as i cut it i loose marks.
condense what you are saying and don't waste space with big words and wordy sentences, long-winded sentences. Maybe not cut out points but rather condense what you're saying in each of these points? hope that helps.