London shares lose 5% during 2015
The 100 share index has ended the year lower than it started, for the fourth time in the past 10 years.
In the traditional half day New Year's Eve session, the index closed at 6,242, down 32 points or 0.5% on the day, and 5% down on the start of the year.
The market's fall has been due to the preponderance of international gas, oil and mining shares in the 100 index.
Their businesses have been hit by the huge drop in commodity prices in the past year.
The FTSE-100 index has also ended the year 12% below its record level recorded in April this year of 7,104.
Steve Clayton, head of equity research at the investment firm Hargreaves Lansdown, said: "It has been a fairly polarised year - weakness in share prices has been a second-half phenomenon."
"Staying away from the mining and energy market stocks, it has been a quite an even story," he added.
The value of the 100 share index also fell in the calendar years 2008, 2011 and 2014.
According to figures from the Bloomberg financial information service, £100 invested at the start of the year in the broader FTSE All-Share index, which covers all publicly listed companies, would now be worth 2% less.
But if dividends from those shares had been reinvested then a shareholder would still have seen the value of their holdings rise by 1.4% in the past year.
This reflects the fact that the income from share dividends across the whole of the UK stock market currently offers investors a yield of more than 3.5% year.
This is highly attractive compared to the nugatory returns that savers receive on their short- and medium-term cash savings accounts.
"If you have been trying to live off your interest you have been living from hand-to-mouth" Mr Clayton said.
According to Ben Kumar, at Seven Investment Management, outside of the mining and energy sectors it has in fact not been a bad year for stock market investors,
"Shares in the FTSE 250 index [covering the 250 biggest shares beyond those in the 100 index] have risen by about 8.5% this year, as the index is based more on consumer and UK focussed stocks", he said.
"By comparison, only 25% of FTSE 100 revenues come from the UK," he added.
But Steve Clayton at Hargreaves Lansdown pointed out that investors relying on dividend income might suffer a "sting in the tail" from the fall in revenues faced by the big gas, oil and mining firms.
These have traditionally been big dividend payers.
"These sorts of companies make up 13% of the All-Share index, and their dividend yields are running high at the moment," Mr Clayton said.
"But this year both Glencore and Anglo American abolished their dividends [to save cash] which shows that other firms' dividends may be cut too."