Engagement, according to the survey, is an important key in savings. Why? Engaged participants say they use tools and information from their 401(k) provider's website to make financial and retirement decisions, feel more confident about saving enough in their DC plans (63% vs. 28%), and rate themselves higher when it comes to financial knowledge (44% vs. 15%).

So what is the role of plan sponsors to provide, maintain and grow engagement for participants?

Let's first consider auto-enrollment. The survey notes that this feature has helped increase overall participation rates by two times that of plans that don't offer it. But there is a caveat. Engagement suffers somewhat with an auto-enrollment feature. Plans without auto-enrollment have higher engagement rates than plans that do have it. But plans without it have lower participation rates. It's a trade-off plan sponsors will have to consider when adding the feature to their plan and how best to maintain full engagement with participants.

Another thing that does help is auto-escalation. The Empower Retirement report says that the feature helps increase both engagement and savings rates. Says the report: "Setting the starting auto-enrollment savings rate high enough to put employees in a position to save enough for retirement can be challenging. The auto-saving rate and employer match may make employees feel like they are saving enough. In fact, more than in six in 10 employees say their savings rate is based on either the employer match or automatically set by the plan."

The good news for plan sponsors is that engagement equals results. Total engagement rate with retirement planning is up two percent from 65% to 67% over the past year. Also, people engaged in their retirement planning save around 61% more than those who aren't engaged (9.2% vs. 5.7%). The differences are significant across all income segments but especially significant for those making less than $60,000 a year.

Besides things like auto-enrollment, and offering investments that appeal to the average investor (such as target-date funds, which actually lowers engagement because of their passive nature), plan sponsors have a duty to provide other services that make engagement easier. Plan provider websites, something that plan sponsors can educate their employees about, offer a great resource to those employees.

The survey reports that more than half (52%) of people said they used tools and information from their provider's website to make financial decisions. As web interactions rise, so do savings rates. There is a difference between people with no interactions compared to people with more than 20 interactions. With a 12% savings rate, participants with more than 20 interactions a year save twice as much as participants with no interactions in a 12-month period. Also matching contributions are another step towards retirement goals.

For plan sponsors interested in helping their participants not only engage with their plan but help boost their savings, a comprehensive approach is the best strategy. That strategy needs to include education, guidance and advisory services, easy-to-use default (and other) investments, and websites that are practical. For the plan sponsor, it starts with enrollment but has to move on from there. As engagement grows, notes the survey, and multiple resources are used, savings rates grow even faster within their retirement savings plans.