It wasn't easy hitting that retirement number. But it wasn't complex, either. You spent less and saved more.

Now it's time to draw a paycheck from the nest egg — and it doesn't look so simple.

You could buy an annuity, but you will give up the flexibility to draw more funds during unexpectedly expensive years. You could build a bond ladder, but yields are still very low. You could assign buckets of assets for future years, or manage withdrawals according to the 4 percent rule or a similar strategy that aims to preserve a portfolio with a given probability of success.

Now, investment management firm BlackRock is launching a retirement income strategy through its network of about 70,000 financial advisers that attempts to mirror the stability of a pension (though there is no actual guarantee) while letting a retiree keep control of his or her assets.

The strategy, part of the firm's iRetire platform, is based on the company's cost-of-retirement index.

Using a simple graphics-based program, advisers can walk clients through a series of decisions aimed at finding a range of income the client is comfortable spending each year in retirement.

Depending on market performance, suggested portfolio withdrawals in a given year might be anywhere in that range.

If the client can stick to those spending levels, the idea is that no matter what happens going forward, he or she could still buy an annuity the following year and lock in a predictable standard of living.

The company hasn't yet laid out complete details of the strategy, but essentially it uses a concept known as liability-driven investment, similar to how the old defined benefit pensions were invested to meet retiring workers' promised monthly benefits.

An unrelated company called Asset Dedication LLC in San Francisco uses liability-matching strategies to create portfolios with specific time horizons.

Like the BlackRock offering, these strategies are created for advisers to use with clients.

The moves come as financial advisers seek new ways to justify their performance fees to clients and stand out from the automated investment services known as robo-advisers.

Essentially, the process marries BlackRock's Aladdin investment platform for advisers with its suite of retirement income indexes, known as CoRI.

"This is really about helping people better understand how much they can safely spend," said Chip Castille, who is BlackRock's chief retirement strategist.

Janet Kidd Stewart writes the Journey for Tribune News Service.