The Arctic sea ice melts and expands in an annual cycle, with the point of least coverage being in September. If you look at graphs showing the extent of sea ice coverage at some particular month of each year since records based on satellite data began in 1979, there is a downward trend. But if you look at just the last twelve year period (since 2002), you could draw a straight line "average" through those points. Or if you just looked at the period 2006-2014, you could draw an upward trend line, showing increasing coverage of ice, rather than a decline. So, other than the melting and expanding that occurs seasonally, it cannot be deduced from the data that the Arctic ice is presently on the decline.
As for what the ice coverage was earlier than 1978, one should be careful what data one uses. The Anthropogenic Global Warming supporters, as represented by the IPCC, have made a habit of practicing bad science and cherry-picking the data. James Delingpole's book
Watermelons (2011) is I think a good introduction to the Climategate scandal and the corruption of good science. The AGW is a billion dollar politicized industry, which gets enormous media coverage for claims which can be fairly dubious though they make good headlines. For example, Delingpole notes how in the
Observer newspaper it was reported in 2007 that the Arctic's sea ice had declined so much that the North West Passage had opened up for the first time since records began [in 1978], yet Roald Amundsen took a ship through this passage in 1903, and the Royal Canadian Mounted Police regularly went through the North West Passage during the 1940s.
The IPCC terms of reference don't even include within their mandate investigating things like the Mediaeval Warm Period, when Arctic ice would have been even less than it has been in the 20th-21st centuries.