Hi Agata,
At the moment, Design Studio doesn't include an equivalent of the Xcelsius Trend Analyzer component. You need to perform such calculations in the back-end, assuming it's practical from a performance perspective. The following discussions may give you some ideas:
Linear Regression Trendline in Design Studio
Plotting a Time Series and a Trend Line
The What-If component Nithya has suggested probably will not meet your requirement because as far as I know it does not perform trend calculations such as linear, logarithmic, polynomial, power and exponential like the Trend Analyzer.
Regards,
Mustafa.