In recent years manufacturers have expanded their product portfolios in a bid to exploit untapped areas of the market and gain crucial market share, according to JATO Dynamics, the automotive data and intelligence provider.
In the last twenty years the market has seen the birth of the MPV (multi-purpose vehicle), SUV (sports utility vehicle), MAV (multi-activity vehicle) and the rise of the 'recreational' 4x4.
Indeed, many of these niche segments have split even further into 'sub-segments'. The SUV market now has products slotting into 'small SUVs', 'medium SUVs, 'large SUVs and 'luxury SUVs' each one further refining the segment and drawing buyers from the traditional, established market segments.
The upper medium segment has been steadily declining for several years and so far this year the volume end of D-segment is a further 17.7% down during the period January to April.
Even the stronger premium end of the D-segment (incorporating models like the BMW 3-Series and Audi A4) is suffering with a 3% decline in the same period.
There are numerous factors that contribute to these figures - not least the fact that two of the key models in the segment, the Ford Mondeo and Renault Laguna are in the run-out stage prior to replacement.
"With manufacturers employing ever more sophisticated marketing techniques, consumer demands are becoming increasingly complex and many families now seek vehicles that better reflect their lifestyle aspirations," said Nasir Shah, international sales & marketing director of JATO Dynamics.
"This has been one of the key drivers behind the success of the SUV and MPV markets where vehicles offer greater flexibility and greater scope for tailoring to individual requirements," added Shah.
New mid-size entrants into the MPV segment such as Ford's S-Max, the Mazda5 and the Citroen Grand C4 Picasso have expanded the segment even further and have contributed to further migration from other more traditional segments.
MPVs remain popular in Europe's 'big five' markets and this popularity is likely to put the established hatchback and saloon markets under continued pressure.