Covid-19 case rates for most regions of England have dropped to their lowest level since September – but there are signs the downward trend may have come to a halt.

Six of the nine regions are recording rates last seen in September, with the North East at its lowest level since September 17 and the North West at its lowest since September 9.

The pace of the drop has slowed in recent weeks, with many regions showing only a very small week-on-week fall in the latest figures.

One region, Yorkshire and the Humber, has even seen its rate rise over the past fortnight.

The figures, compiled by the PA news agency using Public Health England data, suggest case rates might have reached a “floor” in most parts of England, below which they are unlikely to fall much further.

Rates are flatlining at levels higher than the floor reached last summer.

Lockdown restrictions in England are due to be eased slightly from March 29, with two households or up to six people allowed to meet outdoors, the reopening of outdoor sport and leisure facilities, and the formal end of the “stay at home” rule.

The South West has the lowest regional rate in England, with 27.7 cases per 100,000 people for the seven days to March 19.

This is down week-on-week from 32.3 cases per 100,000, and is the lowest rate for the region since September 29.

In London the rate is 35.0, down week-on-week from 39.6 and the lowest since September 23.

Rates in the East Midlands (75.3, down from 80.2) and West Midlands (65.0, down from 67.1) are at their lowest since September 30 and 21 respectively.

In the North East (71.6, down from 77.8) and North West (69.1, down from 75.2) rates are at their lowest for more than six months.

The week-on-week drop is smaller for the South East, down from 37.3 to 33.8 – the lowest since October 2 – and for eastern England, where the rate is almost unchanged (down from 43.9 to 43.1) and the lowest since October 4.

Yorkshire and the Humber is the only region recording a rise, up from 99.4 for the week to March 5 to 107.9 by March 12, and to 108.5 by March 19.

This is the highest regional rate in England.

Six of the 10 local areas with the highest rates of new cases are in Yorkshire and the Humber, including the highest rate in England, which is Barnsley at 193.6 cases per 100,000.