The Speculative Sentiment Index (SSI) is a proprietary tool offered by FXCM. Many technical indicators, such as moving averages, use past data and in a certain sense look in a backward fashion to understand trends. The SSI, however, analyses current data and is considered a leading indicator, meaning it can often signal a change in market The Speculative Sentiment Index (SSI) is a proprietary tool offered by FXCM. Many technical indicators, such as moving averages, use past data and in a certain sense look in a backward fashion to understand trends. The SSI, however, analyses current data and is considered a leading indicator, meaning it can often signal a change in market The Speculative Sentiment Index (SSI) provides a ratio of buyers to sellers on a given instrument. This data is typically used to build strategies on the overall behaviour of retail traders, and is often used as a contrarian indicator.