面板数据画散点图

求助一个面板数据画散点图的问题，一般都是普通的x-y的散点图，有什么办法在这个x-y散点图里面体现出时间趋势吗？

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1. * Example generated by -dataex-. To install: ssc install dataex
   
2. clear
   
3. input byte provcd int year float(x y)
   
4. 32 2012 .469       .037
   
5. 32 2014 .409  .02999997
   
6. 32 2016  .43 .013000011
   
7. 33 2012 .463       .042
   
8. 33 2014 .378 .012000024
   
9. 33 2016 .386 .026000023
   
10. 34 2012 .505  .07599998
    
11. 34 2014 .464 .027999997
    
12. 34 2016 .476 .027999997
    
13. 35 2012 .512  .04799998
    
14. 35 2014 .466 .032000005
    
15. 35 2016  .48  .04699999
    
16. 36 2012 .443  .07700002
    
17. 36 2014 .455  .04400003
    
18. 36 2016 .466 .026000023
    
19. 37 2012 .524  .07099998
    
20. 37 2014 .492 .035000026
    
21. 37 2016 .514 .014999986
    
22. 41 2012 .486       .083
    
23. 41 2014 .429 .065999985
    
24. 41 2016  .48  .07099998
    
25. 42 2012 .421  .02399999
    
26. 42 2014 .418  .04299998
    
27. 42 2016 .437  .04000002
    
28. 43 2012 .494  .11400002
    
29. 43 2014 .433       .037
    
30. 43 2016 .457        .06
    
31. 44 2012 .486       .083
    
32. 44 2014 .414  .04299998
    
33. 44 2016 .445       .046
    
34. 45 2012 .527 .073000014
    
35. 45 2014 .476 .013999999
    
36. 45 2016 .527  .08700001
    
37. 50 2012 .561  .07200003
    
38. 50 2014 .477 .013999999
    
39. 50 2016 .505  .02999997
    
40. 51 2012 .555       .348
    
41. 51 2014 .497  .06099999
    
42. 51 2016 .539  .12699997
    
43. 52 2012 .535  .23799998
    
44. 52 2014 .499       .051
    
45. 52 2016 .581  .06400001
    
46. 53 2012 .522  .12400001
    
47. 53 2014 .484 .022000015
    
48. 53 2016 .579       .078
    
49. 61 2012 .501       .241
    
50. 61 2014 .445  .05800003
    
51. 61 2016 .494  .05500001
    
52. 62 2012 .501  .14600003
    
53. 62 2014 .458       .079
    
54. 62 2016 .506       .042
    
55. end

复制代码

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Listed 51 out of 75 observations