BOSTON — Employees in Massachusetts are paying substantially more toward their health insurance premiums, covering a larger percentage of their premiums, and also paying higher out-of-pocket deductibles, newly released state data shows.

The 2018 average total monthly premium in Massachusetts was $617 for single coverage and $1,687 for family coverage, according to a report released Wednesday by the Center for Health Information and Analysis. The 2016 average monthly premium was $538 for single coverage and $1,487 for family coverage.

The report, compared to CHIA's report on 2016 data, also showed increases in other employee health care costs.

In 2018, the average employee contribution was 26% for single coverage and 30% for family coverage. In CHIA's report on 2016, the average employee contribution for single coverage was 23% that year, and 25% for family coverage.

Among firms offering plans with deductibles, the average annual deductible for single coverage in 2018 was $1,508, slightly lower than the national average of $1,573. In 2016, the average annual deductible for a single coverage health plan in Massachusetts was $1,065, according to CHIA data.

Some 71% of Massachusetts employers offered health insurance to their employees in 2018, up from 65% in 2016, according to the new report, which said 57% of U.S. employers offered employees health insurance.

While seven in 10 employers offered health insurance last year in Massachusetts, only 51% of Massachusetts employees received coverage from their employers, lower than the national coverage rate of 61%. Some employees are covered under the health plans offered by their spouse's employer.

Some 67% of Massachusetts employees who were eligible for their employer's insurance chose to enroll in a plan, which was lower than the national take-up rate of 76%, and followed the national decline in take-up rate between 2016 and 2018.

Among firms with between three and 199 employees, 70% offered insurance compared to 99% of firms with 200 or more employees, according to the report. According to the report, employers most commonly cited employee retention and recruitment as important reasons for offering health insurance.

According to the report, the most common reasons companies gave for not offering insurance were the company was not required to due to its small size, employees were covered under another plan, most employees were part-time or temporary, or costs were too high.

Analysts found the overall coverage rate among part-time workers in Massachusetts was just 10%, which the report says may be attributed "employers setting eligibility requirements for insurance coverage and employees choosing not to enroll in their employer-sponsored insurance as a result of alternative options or lack of affordability."