However, I've been in this game long enough to know that the majority of job seekers don't like to discuss this at interview. They don't want to be the first person to mention a figure. If it's too low, they may miss out financially. If it's too high, they could miss out on a job offer.

If a recruitment consultant asks you this, then I would advise you be as open as possible. They will give you advice on the market rate for your skills and will often do the negotiating for you when you get offered a role. They need to know where your expectations are, so not to waste your time with lower paid jobs in the future.