(Bloomberg) -- The apparent resilience of Hong Kong’s equity market faces a big test as markets reopen Tuesday.

Stock traders in the city, who were off on Monday for a holiday, have yet to react to the latest wave of declines across the border. While the benchmark Hang Seng Index has lost 3.9% in May, its performance stands out against the 6.3% decline for the CSI 300 Index. Mainland shares fell 1.7% Monday after trade talks with the U.S. ended in stalemate, while the offshore yuan weakened past 6.9 per dollar for the first time this year.

Selling pressure on Hong Kong assets is likely to increase as escalating tensions between Beijing and Washington make investors more jittery, while a weaker yuan weighs on earnings for Chinese heavyweights listed in the city. Investors were unprepared last week for the sudden surge in volatility, with hedging costs near the lowest in 15 months.

Below are four charts showing the strain that’s building in the city’s shares.

A slump in China’s currency tends to weigh on Hong Kong’s equities. Morgan Stanley last year estimated that members of the Hang Seng Index generate about 60% of their earnings in yuan. The offshore rate has weakened for six straight days, taking its decline in May to about 2.4% against the dollar.

Short selling turnover in Hong Kong’s main board has been increasing since early May. It accounted for about 15% of total turnover in the city on Friday, the highest in more than two weeks.

The Hang Seng gauge is showing its strongest downward momentum since a sell-off in October, according to a technical indicator known as the directional movement index. The measure -- a tool to assess price direction and strength -- also shows a widening gap between the Hang Seng index’s bullish momentum (in green) and bearish momentum (in red).

Another momentum indicator also points to further declines in Hong Kong. The moving average convergence divergence line -- which in April triggered a bearish signal -- fell even further last week to turn negative. It has also started to decouple from the Hang Seng Index, a pattern known as a “bearish divergence.”

©2019 Bloomberg L.P.