Home Office figures show that of the 19,637 investigations concluded in the region between April and June, just 1,533 resulted in charge or summons – 7.8 per cent.
This was down from 10.9 per cent during the same three months in 2020, and the lowest level for the period since comparable records began in 2014.
Of the investigations closed in West Mercia between April and June, 44 per cent were for violence against the person – the most common type.
This was followed by theft offences – 25 per cent, and criminal damage and arson at 11 per cent.
Across England and Wales, the proportion of offenders charged or ordered to be in court fell over this period from 9.4 per cent to 7.6 per cent, which was also a record low for the quarter.
The charity Victim Support said the low volume of suspects taken to court has been a "major issue" for a long time, and it has been exacerbated by the Covid-19 pandemic.
Jeffrey DeMarco, assistant director at the support service for victims and witnesses of crime, added: “This has the real potential of seriously impacting victims’ security and wellbeing while also damaging trust and confidence in the wider criminal justice system.
"It can also make moving on after being victimised even more difficult."
Stephanie Boyce, president of The Law Society of England and Wales, said the backlog means cases may take years rather than months to reach court.
She added: “Because memories fade over time, there is a risk that evidence given in court will not be as good as if cases were brought promptly, which may affect the outcome.
"It could mean that cases are dropped, for example if victims decide they are no longer prepared to go through with the case."
A Government spokeswoman said changes in charge rates are likely to be the result of more crimes being recorded by police and forces taking on more complex cases which could take longer to resolve.
She added: “We kept the system moving in the most challenging of circumstances, but we are determined to do more to deliver change across the entire criminal justice system.
“Our Beating Crime Plan works collaboratively with police, courts, prison and probation services to drive down crime and protect victims – and we will hold our operational partners to account, to ensure victims’ perpetrators are brought to justice.”