One-quarter of sexual assaults reported to gardaí last year related to incidents that happened more than a decade ago.
New data on serious crime victims released by the Central Statistics Office shows 83% of reports related to incidents which occurred when the victim was in childhood, with victims waiting an average of 20 years before coming forward.
The report indicates men are more likely to be victims of homicide and assault but the overwhelming majority of victims of sexual crimes are women.
Homicide victims were male in 77% of cases and 59% of victims of reported physical assault and related offences were males.
In 2018, there were 2,771 reports of sexual violence with 63% related to incidents that had taken place within one year. Almost 90% of the victims were female.
The remaining 37% of victims (1,017 people) reported offences which occurred more than one year prior to their reporting to An Garda Síochána.
Nine out of ten victims of recent sexual violence reported in last year were females.
Some 33% of victims of recent sexual violence crimes reported in 2018 were females aged between 18 and 29 years at the time of the offence, a further 32% were females aged under 18 years, and 24% were aged 30 or above.
The number of male victims of recent sexual crimes was 192 but, within this group, the victim was under 18 in 58% of cases, compared to 36% for female victims.
The Rape Crisis Network (RCNI) welcomed the level of detail provided in the report.
Clíona Saidléar, RCNI executive director, said: "As sexual violence is highly gendered, with women and children being the majority of the victims and males accounting for the majority of perpetrators, it is vital we understand this if we are to work on successfully preventing sexual violence.
"We can also now for the first time distinguish the current crimes from the crimes committed in the past and the length of the interval between the crime occurring and being reported.
"This is vital, as sexual violence is different to most crimes in how and when people come forward and report."
If you or someone you know has been affected by rape or sexual violence we are here to help. Find you local Rape Crisis Centre here https://t.co/gzOa1nm67t— Rape Crisis Network (@RCNIreland) April 17, 2019
The CSO data also noted there were 57 male victims (77%) and 17 female victims (23%) of homicide recorded in 2018 - 46 were victims of murder or manslaughter, 78% were males, and 28 were victims of dangerous driving leading to death. Three-quarters were male.
There were 18,939 reports of assault and related offences, which includes attempts or threats to murder and harassment.
Figures show 59% of physical assault victims were male, 32% of victims of assault and related offences were aged 18-29, with a further 32% aged 30-44.
And 14% were under 18, with 5% aged 60 or above.
While one-quarter of sexual assault reports related to historic incidents, fewer than 1% of reports of assault or related incidents in 2018 related to incidents which occurred more than a year previously.
The figures are published under reservation meaning the Central Statistics Office still has concerns about the quality of An Garda Síochána’s recorded data.