A sinking stock market and worries about falling oil prices are weighing on investors. The result? Client appetite for risk has significantly lessened.

These factors brought the Retirement Advisor Confidence Index — Financial Planning’s monthly barometer of business conditions for wealth managers — into negative territory after two months in the black. A holiday lull also helped push the indicator lower.

Advisors are noting that clients are significantly more risk-averse. The index’s risk tolerance barometer dropped 17.3 points to 34.8 after reaching 52.1 the month before. Clients moved toward cash and away from equities: Allocations to equities dropped 11.1 points to 48.4.

Several advisors worried their clients’ hesitant behavior may not bode well for 2016. “There is an increasing cautiousness,” one advisor said. “And it was during December and most of the last half of 2015 that the shift has occurred.” Another advisor noted possible factors driving down client confidence: “The economy seems spooked about China and lower oil prices. ”

Some welcomed the lull, readying themselves for more business before tax season. “The end of the year is relatively quiet in that we were not establishing new accounts,” one advisor wrote. “I expect some increase in February/March as we prepare for the tax deadline.”

This month’s results also include the Retirement Readiness Index, which asks advisors to track their clients’ retirement preparedness. The analysis tracks client-related factors, including their current retirement status, income replacement ability, dependence on Social Security and vulnerability to big economic shifts.

The data, which track activity over the previous quarter, found 67% of mass affluent clients were somewhat or extremely vulnerable if a significant rise in health care costs occurred. “Health care costs are the biggest single expense in retirement; most savings are used to cover supplemental medical and medical delays many people’s retirement ages and lifestyle expectations,” wrote one advisor.

Another finding was that over 30% of high-net-worth clients would be hurt by a big decline in the equities market.

Advisors also reported they were confident over 50% of their mass affluent and high-net-worth clients would be able to replace income for 30 years by the time they retire, but only 23% of ultrahigh-net-worth clients would be able to replace their income under the same parameters.

The Retirement Advisor Confidence Index consists of 10 factors — including asset allocations, economic and risk factors, taxes and planning fees — to track trends in wealth management. RACI reading below 50 indicate deteriorating businesss conditions, while readings over 50 signify improvements.