How to create multiple trend lines without clicking on each line in the graph

[ExcelNoob101]

I am trying to create a trendline for multiple series. Is there a way to "create trendline for all series"? I have also tried to use the linest function to get the trendlines but it does not work because I have gaps in my data. Below is an example of my data which I would like to create a polynomial degree 6 trendline for (or get the equation for the trendline). I know I could remove the gaps or add a trendline one by one, but I would like to find a faster way to do this because I will have a much bigger table than what I am providing for this example. Any help would be appreciated. I have spent quite a while trying to find this out on my own. I know this example data does not need polynomial degree 6, but the data that I am actually needing it for has about 250 Y values and does require a higher degree polynomial. Thanks in advance and here is a sample table:

[TABLE="width: 500"]
<tbody>[TR]
[TD]Y Value[/TD]
[TD]X1[/TD]
[TD]X2[/TD]
[TD]X3[/TD]
[TD]X4[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD][/TD]
[TD]-64[/TD]
[TD]-66[/TD]
[TD]-63[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD][/TD]
[TD]-64[/TD]
[TD][/TD]
[TD]-64[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]-65[/TD]
[TD][/TD]
[TD]-63[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD][/TD]
[TD]-59[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]6[/TD]
[TD]-68[/TD]
[TD][/TD]
[TD][/TD]
[TD]-61[/TD]
[/TR]
[TR]
[TD]7[/TD]
[TD]-61[/TD]
[TD]-62[/TD]
[TD]-57[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]8[/TD]
[TD]-69
[/TD]
[TD]-57[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]9[/TD]
[TD]-63[/TD]
[TD][/TD]
[TD]-54[/TD]
[TD]-62[/TD]
[/TR]
</tbody>[/TABLE]