I'd appreciate some help with my data. I have to find (S)ARIMA models to fit some exportations data, but for some of them, I can't find an easy model by just looking ACF and PACF plots. So I change randomly $p,d,q$ and $P,D,Q$, but some data are really difficult to fit. Here is an example, I spent hours at modifying parameters, and don't find a good model with significant coefficients and good ACF et PACF plots of residuals. Here are pictures of time serie of exportation, and PACF (I could not post ACF because I don't have enough reputation to post more than 2 links, but nothing was significant).
I am super interested if someone could give me a good model, because I feel like I will never find a good one. But I am even more interested in understanding how you find a good model for that kind of complex data. Here are the data. Thanks in advance.
- 22,04761905 - 21,36363636 - 20 - 22 - 19,19047619 - 21,81818182 - 18,68421053 - 22,9047619 - 20,38095238 - 21,27272727 - 20,68181818 - 18,6 - 17,39130435 - 19,86363636 - 18,68421053 - 20,42857143 - 19,1 - 21,2 - 19,19047619 - 21 - 19,8 - 22,52173913 - 19,52380952 - 18,52380952 - 18,7826087 - 21,9047619 - 15,45 - 23,38095238 - 22,05 - 20,57142857 - 19,5 - 18,80952381 - 18,9 - 19,86956522 - 17,55 - 18,18181818 - 22,69565217 - 19,5 - 19,23809524