A few questions:
1. Where did this data come from? It looks entirely too smooth to be a real-world signal.
2. What's the independent variable name? Dependent variable name?
3. Do you think the data approaches a slant asymptote as the independent variable goes to positive infinity?
4. What do you want to do with this data? Interpolate? Extrapolate? If the latter, how far out do you want to go?