erratic index

例句：

1. 1. The erratic index of the stock market fluctuates widely.
   股市的不规则指数波动很大。
2. 2. The irregular index is used to measure the deviation from a normal distribution.
   不规则指数用于衡量偏离正态分布的程度。
3. 3. The erratic index has been causing concern among investors due to its high volatility.
   由于其高波动性，投资者对不规则指数感到担忧。