The phrase "the trend values" is correct and usable in written English.
You can use it when referring to the values that define a certain trend or development. For example, "The trend values for 2020 denote a shift toward a more conscious lifestyle."
The trend values are -4 × 10-3 MHz/year if only solar minimum periods are considered and -5 × 10-3 MHz/year for periods of solar maximum.
The choice of the model or solar EUV proxy may affect the trend values as long as the model or proxy selected does not effectively reflect the real variance of foF2 due to the solar EUV radiation, which is the part one wants to filter before trend determination.
In IDCs without nodal metastasis, the pTNM and HG classifications could not significantly increase the trend values for the HRs of tumour recurrence or death in the multivariate analyses, but a significant increase in the trend values of the HRs of tumour recurrence was observed for the NPI classification in multivariate analyses with the PVN classification in IDCs positive for ER and/or PR.
In the multivariate analyses, the PVN classification significantly increased the trend values for the HRs, 95% CI, and the P-values for disease-free and overall survival when compared with other prognostic classification systems (Table 4).
On the other hand, other prognostic classification systems failed to significantly increase the trend values for the HRs, 95% CI, and the P-values when compared with the PVN classification.
However, in IDCs negative for both ER and PR, the NPI classification failed to significantly increase the trend values of the HRs of tumour recurrence and death in the multivariate analyses with the PVN classification.
The length of the period considered is related to the stability of the trend value in terms of the time series length.
This situation results in persistent negative residuals which will affect the trend value according to where this period of persistence is located within the whole period of analysis.
However, when solar cycle 23 begins to be included in the trend estimation, the trend value becomes less negative or even positive when Rz instead of F10.7 is used to filter out solar activity effect.Figure 8 shows the running foF2 trend using a window of 20 years.
To highlight the overall trend, values were smoothed for the observed data by averaging values over a 50 kb sliding window.
In the case of experimental trend values, they are negative first and become less negative as solar cycle 23 is included in the trend estimation.
