The 40-year bull market in the bond market is under pressure as Treasury yields hit the "most important trend line in history".

Carter Braxton Worth, a technical analyst at Worth charting, saidThe 40-year downward trend in interest rates may be coming to an end as 10-year Treasury yields hit the resistance level of the "most important trend line in history".

Bond prices rise as interest rates fall. At a time of record inflation and economic expansion, the Fed is raising interest rates to help cool demand and curb inflation.

Today, the widely watched 10-year Treasury yield is approaching its 40-year downward trend line. The trend line began with interest rates peaking at 15.81% in 1981.

Worth tweeted last week:

The long-term trend line drawn based on complete historical data is the most important trend line for 10-year US Treasury yields, as is the case in any market.

It is so important because whether 10-year Treasury yields rise or fall will have a broad impact on the overall pricing of equities and risky assets.

Worth believes that if 10-year Treasury yields break through its 40-year downward trend, it could be seen as the beginning of a new upward trend. This will mean that interest rates will continue to rise and share prices will continue to be under pressure.

But if 10-year Treasury yields show no sign of rebounding on the downward trend line, interest rates may be expected to stay lower for a longer period of time, which could help boost risky asset valuations and push up share prices.

Worth said in an interview with CNBC on Monday:

This is exactly the same trend line since its peak in 1981, which works at 2.81%. Our reaction to this line really determines whether we will hold back because of the impending recession, or whether we will really break through in a meaningful way.

He added that he did not think there was much room for the rate to rise.

If Worth's assessment is correct, it will be a welcome signal for stock market investors. Earlier this year, the s & p 500 had suffered a correction of more than 10%.

The 10-year Treasury yield is now hitting a high of 2.866 per cent, slightly higher than the 2.81 per cent yield closely watched by the Worth.Unless the interest rate stops rising quickly, the stock market is likely to become more difficult.

The Fed plans to raise interest rates by 50 basis points in May, which could end the 40-year downward trend in 10-year Treasury yields and start a new long-term upward trend. This effectively ended a decades-long bull market in bonds.

Previous data from Bloomberg also suggested that the 40-year bull market in U. S. debt may have come to an end. A Bloomberg measure of the total return on US debt is down nearly 8 per cent this year, and as market bets on raising interest rates increaseThe measure is on track for the biggest annual decline since at least 1973, which could mark the end of a 40-year bond bull market.