Average rail fares across the UK will increase by 2.2% from January, it's been announced.

A combination of low inflation and a change to the cap on fares means it's the lowest increase for five years, says industry body the Rail Delivery Group.

How rail fare increases are decided

The average figure covers both regulated and unregulated fares.

Regulated fares include season tickets, off-peak return tickets and walk-up anytime single tickets.

These tickets are regulated by the Government in line with July’s Retail Prices Index (RPI) measure of inflation.

Since 2004 regulated rail fare increases have been calculated using July’s RPI+1%. This is so passengers pay a bigger portion of the cost of running the railways than taxpayers.

However, for the second year running the Government altered its preferred calculation so the increase was pinned only to inflation, amid growing anger from commuters at high fares.

It also scrapped the flex rule, which allowed train companies to vary price increases by 2% above RPI across their routes on individual journeys.

Regulated fares will rise by 2.5% in England and Wales. In Scotland peak fares will go up by 2.5% but off peak fares will be frozen for the second year running. In Northern Ireland, regulated fares are set separately and have not risen since 2013.

Rail operators are allowed to set the price of other fares, known as unregulated fares, as there is greater competition.

The Rail Delivery Group says discounting by train companies had contributed to the number of train journeys doubling since the mid-1990s. In 2012-2013, 47% of passenger revenue came from discounted tickets, up from 36% in 2002-2003.

[Related story: Autumn Statement: the main announcements]

How train companies spend our money

According to the Rail Delivery Group rail operators only make 3p of profit from every pound.

Below is how the costs breakdown.

Service Proportion per £1 Investment in the rail network 26p Maintaining track and trains 22p Industry staff costs 25p Interest payments and other costs 9p Leasing trains 11p Fuel for trains 4p Train company profits 3p

Source: Rail Delivery Group

Michael Roberts, Director General of the Rail Delivery Group which represents rail operators and Network Rail, said: “Money from fares goes towards running and maintaining the railway. This benefits not just passengers and businesses but communities across the country, by improving journeys, creating employment and helping to boost the economy.

“Over the next five years, Network Rail is spending on average £27million a day on a better railway, alongside commitments made by train companies to improve services. That will mean more seats, better stations and improved journeys.”

See how you are impacted

From today fares for travel from 2nd January 2015 are available to check and buy, so you can check how your journey is impacted via the National Rail website.

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