Suzeren,

измени формат уравнения линии тренда (увеличь число знаков)
у меня все бьется
y = -6.8819483909E-11x5 + 8.1829939775E-08x4 - 3.8390624663E-05x3 + 8.2984573637E-03x2 - 5.7234492487E-01x - 1.2184442017E+01

1 -13.7 -12.7
6 -15.5 -15.3
11 -17.3 -17.5
16 -18.9 -19.4
21 -20.3 -20.9
26 -21.6 -22.1
31 -22.6 -23.0
36 -23.4 -23.7
41 -24 -24.1
46 -24.4 -24.3
51 -24.5 -24.4
56 -24.5 -24.2
61 -24.2 -23.9
66 -23.8 -23.4
71 -23.1 -22.8
76 -22.4 -22.0
81 -21.5 -21.2
86 -20.5 -20.3
91 -19.5 -19.3
96 -18.3 -18.2
101 -17.1 -17.1
106 -15.9 -15.9
111 -14.6 -14.7
116 -13.3 -13.5
121 -12 -12.2
126 -10.7 -10.9
131 -9.4 -9.6
136 -8.1 -8.3
141 -6.8 -7.0
146 -5.6 -5.7
151 -4.3 -4.4
156 -3 -3.2
161 -1.8 -1.9
166 -0.6 -0.7
171 0.6 0.5
176 1.7 1.7
181 2.9 2.9
186 4 4.0
191 5.1 5.1
196 6.1 6.2
201 7.2 7.3
206 8.2 8.3
211 9.2 9.3
216 10.1 10.2
221 11.1 11.2
226 12 12.1
231 12.8 12.9
236 13.7 13.8
241 14.5 14.6
246 15.3 15.4
251 16.1 16.1
256 16.8 16.8
261 17.6 17.5
266 18.2 18.2
271 18.9 18.9
276 19.5 19.5
281 20.1 20.1
286 20.7 20.6
291 21.2 21.1
296 21.7 21.6
301 22.2 22.1
306 22.6 22.5
311 23 22.9
316 23.3 23.3
321 23.7 23.6
326 23.9 23.9
331 24.1 24.2
336 24.3 24.3
341 24.4 24.5
346 24.5 24.6
351 24.6 24.6
356 24.5 24.5