The over 50s are under no illusions about the cost of retirement. They know they have a mountain to climb when it comes to saving for retirement, and realise that to live in comfort in their golden years they need to set aside almost £100,000. The trouble is that on average they're set to fall short by 70%.

And if you think that's bad, just wait until you hear what a mess the under 35s are in.

Over 50s

Research from HSBC asked people how much they felt they needed to put aside for their retirement, and how much they were currently saving. The fact that the over 50s understood that they needed to save a small fortune is relatively comforting. They said on average that they were aiming to save up almost £102,000.

However, it's fairly terrifying how far they are falling short. Their current average savings pot is just £15,464, and at the current rate of saving, the average person will end up with savings of around £31,000. It means they have a regular savings gap of £10,000 a year.

Younger

Younger age groups have a longer time to make up any shortfall. However, worryingly they seem almost entirely in the dark about the size of a pension pot they'll need to build up. Those aged between 16 and 24, only plan to save £48,000 - which is a drop in the ocean of the sum they will actually need to accumulate.

This group currently has an average savings pot of £4,187. The good news for this group is that they are saving at a reasonable rate, and they have ages until retirement. If they can keep up the good work, then they will actually retire with a pot of £51,587.

Expensive 30s

The bad news is that even though this is more than they are aiming for, it is far short of what they will need, and there's every chance that when they hit the expensive years of their 30s it will all fall apart anyway. After the age of 35, pension savings goes through the doldrums for ten years, as we scrabble around to deal with all the other demands on our cash.

For women, the picture is even more bleak. Women over the age of 55 have lower expectations than men -and are aiming to build up a pot of, on average, £87,000. However, they are set to be an average of £33,000 short - compared to men who are likely to be £3,000 short.

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Bruno Genovese, head of savings at HSBC, says: "The increased financial responsibility that many people face around their mid 30s, such as buying a house, having children and taking on more debt, seems to be hindering long-term savings habits, despite the good intentions. This divides UK savers between younger generations with the potential to meet their long-term savings goals and older generations who have higher and more realistic aspirations but have often left it too late to achieve them."

Distracted

It goes to show just how dangerous it can be to get distracted by other priorities - especially for women who often are not working full time during this period as they take on more caring responsibilities. In many cases, they stop paying into their pensions for ten years or more - which means they will either need to work well into their 70s, or prepare themselves for a horrible shock.

The only answer is to consider pensions savings a priority throughout our working lives. When we're hard-pressed it's easy to see pension payments as the straw that is breaking the camel's back, and tempting to stop them until the tougher times are over. However, while in some cases we may have no alternative, in general we can all find alternative ways to cut our costs. It may be more painful to set our property ambitions lower, or buy a smaller and cheaper car. But in your retirement, you'll look back at the relative luxury you chose in your 30s in horror and regret.

But what do you think? Are you on track? Do you really know what you're aiming for - let alone whether you're going to make it? Let us know in the comments.

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