A monthly gauge of online labor demand in the United States held steady in March, with transportation and retail registering strong growth, the operator of a job search website said on Friday.

Monster Worldwide Inc , an online careers and recruiting firm, said its employment index was unchanged from February at 143. The index was up 5 percent from a year earlier.

The index showed annual growth in 16 of the 20 industries and 20 of the 23 occupations monitored last month.

The report was another look at the jobs market ahead of the government's non-farm payrolls report later on Friday. Economists, on average, expect the report to show that the economy added 203,000 jobs in March, according to a Reuters poll.

The Monster Employment index is a monthly analysis based on a selection of corporate career sites and job boards. The margin of error is approximately plus or minus 1 percent.

(Reporting by Emily Kaiser in Singapore; Editing by Richard Borsuk)