Before revision:  Once the optimal design is selected, the forecast is produced by a linear combination of  the average spin of a 6-qubit quantum register trained using VIX and SPX data from year 1990 onwards.
After revision:  Once the optimal design is selected, the forecast is produced by a linear combination of P500 (SPX) time-series. Our reservoir is a hybrid quantum-classical system executed on IBM's 53-qubit Rochester chip. We encode the SPX values in the rotation angles and linearly combine the average spin of a 6-qubit quantum register trained using VIX and SPX data from year 1990 onwards.