小弟用图形对1995-2007年的专利及FDI值进行描述时，想再附上95%置信区间的图，不知哪位高人知道吗？数据见附件


版主coral033：利用函数confidence，以FDI值为例，请见下面跟帖的附件。
Syntax
CONFIDENCE(alpha,standard_dev,size)
Alpha is the significance level used to compute the confidence level. The confidence level equals 100*(1 - alpha)%, or in other words, an alpha of 0.05 indicates a 95 percent confidence level.
Standard_dev is the population standard deviation for the data range and is assumed to be known.
Size is the sample size.

A B Data Description 0.05 Significance level 2.5 Standard deviation of the population 50 Sample size Formula Description (Result) =CONFIDENCE(A2,A3,A4) Confidence interval for a population mean. In other words, the confidence interval for the underlying population mean for travel to work equals 30 ± 0.692952 minutes, or 29.3 to 30.7 minutes. (0.692952)