The number of people prosecuted for rape in England and Wales has slumped, despite record volumes of cases being reported to police, new figures show.

The annual Violence Against Women and Girls (VAWG) report from the Crown Prosecution Service (CPS) shows there were just 1,925 convictions for rape  or an alternative lesser offence during the financial year 2018-19, down from 2,635 in the previous 12 months – a drop of 26.9%.

This is despite the number of rape claims dealt with annually by police in England and Wales rising from 35,847 to 57,882 during the last four years.

It means around 3.3% of all reported rapes end in a conviction.

Figures show that the charge rate for rape – essentially the decision to press ahead with a prosecution – has dropped from 64.3% in 2014-15 to 48.2% this year.

It represents the first time in five years that the percentage of legal decisions made by the CPS in rape cases has dropped below 60%, according to the data, meaning the percentage of decisions not to prosecute also increased to its highest rate in that time.

Despite an increase in the volume of alleged rapes reported to police, the CPS has seen a reduction in the number it decides to charge every year since 2015-16.

This is a decrease from 3,910 in 2015-16, to 3,671 the following year, then 2,822 last year, and 1,758 most recently.

The report said the number of rape suspects referred by the police to the CPS for a charging decision fell from 4,370 in 2017-18 to 3,375 in 2018-19 – a drop of 22.8%.

The CPS said the “growing gap” between the number of rapes recorded by the police, and the number of cases going to court is a “cause of concern for all of us in the criminal justice system”.

The report said it was not an indication of any change in policy, or lack of CPS commitment to prosecute.

Campaigners have previously argued that the CPS had begun ditching so-called “weak” cases in order to improve notoriously low rape conviction rates.

The CPS said the drop in rape charges was due to “a number of factors”, including reduction in the number of referrals from the police to the CPS, and an increase in the volume of time-consuming digital data.

In the wake of the figures, Director of Public Prosecutions Max Hill – overseeing his first VAWG report – announced that the independent CPS watchdog, Her Majesty’s Crown Prosecution Service Inspectorate (HMCPSI), will hold a review of rape charging decisions “to increase accountability and reassure victims of sexual offences”.

Mr Hill said: “Rape is an awful, sickening offence and I completely understand why the fall in charging rates is so concerning.

“Partners across the criminal justice system are coming together to look at how these cases are handled and the CPS is playing its part by opening up our charging decisions to further scrutiny.

“I have every confidence in the work of our dedicated prosecutors but it is important that the public has confidence too.

“I intend to implement any changes which are recommended if they improve our processes and enable the criminal justice system to deliver swifter, more effective justice.”

Elsewhere in the report, figures show the number of suspects charged by the CPS with offences grouped under the VAWG strand – such as domestic abuse, stalking, rape, female genital mutilation and child abuse – dropped 13.2% from 187,545 to 162,717.

Combined, the number of stalking and harassment offences charged decreased from 11,992 in 2017-18 to 10,636 in 2018-19 – a fall of 10.8%.

The report comes as a coalition of women’s organisations, represented by the Centre for Women’s Justice (CWJ), gets ready to launch a judicial review case against the CPS over claims sexual offences cases are being “dropped” without good reason – something denied by Mr Hill.

Speaking on the BBC Radio 4 Today programme, he said: “There has not been a change in approach from prosecutors at the CPS.

“I absolutely share the concern … at the growing gap between rape reporting levels and the number of cases that are coming to court.

“I am not going to point the finger in any particular direction. We – all of us working in the criminal justice system – need to come together now to discuss this.”

Andrea Simon, head of public affairs at the End Violence Against Women Coalition, which is among those looking to take legal action against the CPS, said: “These numbers represent real women subjected to rape, a crime which does enormous harm, who are then further victimised by a system that does not take them seriously.

“These shocking and unjustifiable failings speak to a clear and concerted shift in how the CPS has decided to prosecute rape.

“Leadership across the CPS needs to answer for these figures which we say can only represent what is becoming the effective decriminalisation of rape.”

Harriet Wistrich, CWJ director, said: “The CPS have repeatedly denied that they have changed their approach to the prosecution of rape.

“They have variously blamed the fall in the number of cases prosecuted on the delays caused by disclosure demand… and on the police for the failure to progress and refer cases.

“However, we have gathered evidence from a variety of significant sources which, taken together, provide a compelling picture that the primary cause of this collapse in prosecutions emanates from a deliberate change in the approach taken by the CPS dating back to late 2016.”