If you’re trying to get a handle on the topsy-turvy retail world, there are two numbers you should pay attention to right now: 0.3% and 0.8%.

The first is the decline of overall U.S. retail sales in May, according to Commerce Department figures released last week, well short of the 0.1% increase economists expected.

The second figure is the growth online retailers saw in the same month.

The King of the Disrupters

The latest snapshot came just two days before Amazon.com (NSDQ: AMZN) shook up the retail world with its $42-a-share deal for Whole Foods Market (NSDQ: WFM). As of this writing, Whole Foods has soared nearly 32% since the market’s close on June 15, just before the news broke, to $43.49 a share, above Amazon’s offer.

That suggests investors expect another suitor to pop up and compete with the online giant for the natural-food retailer, which has 456 stores, the vast majority of which are in the U.S.

But Amazon has plenty of firepower should that happen, with $19.3 billion in cash on its balance sheet, well above the deal’s $13.7 billion value, along with a reasonable $7.7 billion of long-term debt.

Amazon hasn’t revealed its plans for Whole Foods, but it’s almost certain it will use the chain as a pick-up/delivery point for online orders. And that has put paid to a long-held belief about grocery stocks—that they’re a relatively safe part of a sector that’s taken plenty of knocks from web-based competition.

Department stores, for example, have seen their workforces slashed by 46% from 2001 to 2016, raising concerns that shopping malls could go extinct (more on that in a moment).

To date, online sales only make up a small portion of the total yearly U.S. grocery spend, though the latest figures from Nielsen and the Food Marketing Institute portray an industry on the tipping point, with e-commerce expected to jump to a 20% share by 2025.

Investors, predictably, took news of the deal hard. Kroger (NYSE: KR) is down more than 8% since the June 15 close (compounding a 19% swoon after the chain slashed its earnings guidance the day before). Supervalu (NYSE: SVU) has dropped nearly 22% and Wal-Mart (NYSE: WMT) is off by a little more than 5%. By contrast, the S&P 500 is roughly flat.

An Income Conundrum

If you’re an income investor, you may not be losing a lot of sleep over the retail sector’s struggles. After all, this isn’t exactly a high-yield hunting ground: U.S. retailers, as measured by the SPDR S&P Retail ETF (NYSE: XRT), pay about 2.0% on average, right around the S&P 500 as a whole.

But the Amazon/Whole Foods deal has stirred up concerns about one investment plenty of income seekers hold: real estate investment trusts (REITs) that own shopping malls, where grocery stores are often anchor tenants.

For example, Simon Property Group (NYSE: SPG), the largest mall owner by market cap, is down around 1.3% since before the Amazon/Whole Foods deal was announced, while Realty Income (NYSE: O) is off by more than 3%.

But a funny thing happened on the way to the shopping mall’s funeral: the leading retail REITs—in particular those with attractive properties in busy areas—are doing fine.

Simon, for example, saw per-share funds from operations jump 4.2% in the first quarter from a year earlier, and occupancy came in at a high 95.6%. Realty Income, for its part, posted an adjusted FFO gain of 8.6%, along with 98.3% occupancy.

That’s partly because the big landlords are doing a good job of diversifying. Realty Income is a great example: 18.1% of its rental revenue last year came from companies that aren’t even retailers, up from 13.3% in 2012. And the REIT gets just 3.6% of its rental revenue from grocery stores.

Other Income Options

Nonetheless, if you’re concerned about investing in retail REITs, there are other parts of this high-yield sector that are more than worth a look. Some industrial REITs, for example, benefit from online shopping, as they own the warehouses in which the e-commerce players, including Amazon, store their ever-growing pile of wares.

Another possibility? Cell-tower REITs, which don’t directly benefit from e-commerce but do profit from the rising use of mobile data. We recommend two such stocks in our Income Millionaire portfolio.

Meantime, we’ll keep an eye on the evolving retail REIT scene in Income Millionaire and bring you the latest on other income plays not tied to e-commerce (such as a low-key Canadian healthcare REIT no one is talking about) in future issues of both that publication and Income Without Borders.