The number of corporate bankruptcies in Japan involving liabilities of at least ?10 million ($63,000) totaled 851 last month, the highest level in 13 years for a February, Tokyo Shoko Research said Monday.

The figure marked a year-on-year rise of 11.3% and the third consecutive monthly increase, driven in part by worsening business conditions that reflected sluggish sales and growing labor shortages.

By industry, the service sector saw the largest increase, climbing 30.9% to 309 cases. The construction and transportation industries also posted year-on-year growth in the number of bankruptcies.

Sluggish sales were the leading cause of business failures in 625 cases, or 73.4% of the total.

Bankruptcies linked to labor shortages stemming from rising labor costs, retirements and other factors totaled 47, more than double the 19 reported a year earlier.

Total liabilities fell 22.2% to ?133.16 billion. Nearly 80% of all cases involved debts of less than ?100 million, primarily among small companies and microbusinesses.

Oil prices are rising due to escalating military tensions in the Middle East. Tokyo Shoko Research warned that higher energy costs would push up a variety of expenses, saying, ¡°That would be a further setback for companies whose profitability has already been deteriorating due to higher prices.¡±