But now, Hussman notes in his latest market commentary that the ECRI Weekly Leading Index, which has been a leading indicator for the ISM index, has declined to -6.9%, a bad sign.

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The Services PMI index is a key indicator of the European economy, more so than the index for manufacturing.

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Of course, in very strong bull or bear markets, we must rely on technical indicators that can stay with strongly trending markets, as momentum indicators like the Moving Average Convergence Divergence (MACD) indicator or Relative Strength Index (RSI) will top or bottom out well ahead of prices.

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