New figures from the NSW Bureau of Crime Statistics and Research reveal 35 victims of sexual assault in the Illawarra came forward in March this year, a 35 per cent increase on the monthly average over the previous year.

Across NSW, police recorded 940 sexual assaults in March - 300 more than the previous month, and 61 per cent higher than the monthly average.

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The Bureau of Crime Statistics and Research attributed this to greater willingness among victims to come forward, due to a high level of media coverage and public attention on allegations of sexual violence, rather than increased offending.

Executive director Jackie Fitzgerald said only 10 to 15 per cent of adult victims reported such crimes to police.

"The March 2021 increase shows that, under the right conditions, more victims will come forward," Ms Fitzgerald said.

"More now needs to be done to make sure that victims who reach out are appropriately supported."

In the two years to March, the number of sexual assault reports in the Wollongong local government area rose by an average of 28.4 per cent each year.

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There were 155 reports of sexual assault in Wollongong in the year to March 2020, which jumped up to 199 the following year.

Over five years, reports rose on average 10.8 per cent annually.

In Shellharbour, reports remained relatively stable over two years, but in the five years to March there was an average annual increase of almost 12 per cent.

The number of other sexual offences, such as indecent assault, remained steady in Shellharbour.

Over the same five-year period, Wollongong again saw an increase in reports of other sexual crimes than sexual assault - on average, such offences were up by 7.2 per cent per year.

But between March 2020 and March 2021, reports of these crimes dropped by almost 11 per cent.

Kiama saw the number of reports of sexual offences rise from eight in the year to March 2020, to 13 the following year.

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Reports of other sexual offences went up from 11 to 15.

The crime statistics also showed break-ins at homes have dropped in Wollongong and Shellharbour.

Break-and-enters into other buildings have also decreased over the five years to March, although remained somewhat steady over the past two years.

The two municipalities have also seen fewer thefts from vehicles.

The statistics agency said the decline in such offences was associated with the response to the COVID-19 pandemic.

If you or someone you know has experienced sexual violence, call 1800RESPECT on 1800 737 732 for support. In a crisis, help is available from Lifeline on 13 11 14. If someone is in immediate danger, call triple-0.

For information on reporting to police and other options for victims, visit the NSW Police website.

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