What's life like for those hitting the Big Four Oh? There are more forty year olds in Australia than any other age group. And there's more of them than ever before. But what does the big milestone mean these days? Strictly speaking, being 40 is not actually "middle aged" anymore - especially for women, whose life expectancy is now well into the 80s. And while many 40 year olds find themselves hitting their stride, others are confronting some hard facts. They're in the midst of a long mortgage and nearly a quarter of 40 year olds are suffering from mortage stress, where more than a third of their income goes to housing costs. They're also staring down the barrel of declining fertility. A quarter of today's 40 year old women will have no children in their lifetime. However, due to medical advancements, today there are now far more women aged 40 giving birth. And while most 40 year olds are married, around a third have never walked down the aisle. Forty is also the average age for men to separate from their partner. And for single women looking for a partner, it can be tough: there are more 40 year old women than men, so there's a 'man drought' in that age group. This week an audience of 40 year olds from Australia join host Jenny Brockie to share their very personal and diverse stories of what this milestone means in 2011.