CNBC’s Jim Cramer is advising that investors who are searching for entry and exit points keep a close eye on both stock and cryptocurrency trades in the coming weeks.

The “Mad Money” host on Friday reviewed chart analysis from Tom DeMark, the founder and head of DeMark Analytics.

“The charts, as interpreted by Tom DeMark, suggest that bitcoin might take another month to bottom, while the S&P 500 could peak as soon as next week,” he said. “Considering Tom’s track record, that’s a good reason to be patient with bitcoin and approach the S&P with some caution.”

DeMark invented the DeMark Indicator, which some traders use to time the market. The methodology, which follows patterns to project when a trend could change course, is popular among crypto traders to spot highs and lows, Cramer said.

Cramer reviewed the daily chart action for bitcoin, which peaked at around $65,000 in mid-April. The digital coin is now trading above $37,300 as of Friday after falling to $30,000 in mid-May.

DeMark, who said the drop in bitcoin resembles the crash of 1987, projected that the decline could bring the token’s value to a floor of $32,000 — or $24,000 in the worst case. He now thinks that bitcoin will generally hold above the May 19th low, Cramer said.

In what’s known as “Black Monday,” the Dow Jones Industrial Average plummeted more than 20% on Oct. 19, 1987. It was the bookend of a 36% decline in the blue-chip index from August that year.

“If DeMark’s right, you could get a chance to buy bitcoin in the not-too-distant future, and I might take it,” Cramer said. “I think this ’87 analogy is good news. After the crash of ’87, the stock market bounced back fast.”

As for the S&P 500, which closed at a record for the second-straight day, DeMark’s indicator suggests the index could be close to a top, Cramer said. DeMark has price targets of $4,335 and $4,344, about 2% higher than Friday’s finish.