I am very new to Latex and really need help. I am trying to format a longtable such that under the caption I can insert a description of the table. I tried with \multicolumn, but then the first column got really long and the text didn't fit the page. Does anyone have experience with this? Thank you!
\begin{longtable}[c]{p{1cm}p{6cm}p{3.5cm}p{5cm}}
\caption{Overview bank sample \label{Overview sample compilation}}
\hline
\textbf{Rank} & \textbf{Bank name} & \textbf{Home country} & \textbf{Local Index}\\
\hline
\endfirsthead
\hline
\multicolumn{4}{r}{Continuation of Table \ref{Overview sample compilation}}\\
\hline
\textbf{Rank} & \textbf{Bank name} & \textbf{Home country} & \textbf{Local Index} \\
\hline
\endhead
\hline
\endfoot
\endlastfoot
1 & Allied Irish Banks & Ireland & ISEQ20 \\
2 & Banco Bilbao Vizcaya Argentina & Spain & IBEX 35 \\
3 & Banco Santander & Spain & IBEX 35 \\
4 & Bank of America & United States & S\&P 500 \\
5 & Bank of Montreal & Canada & S\&P TSX Composite Index \\
6 & Barclays & United Kingdom & FTSE 100 \\
7 & BNP Paribas & France & CAC 40 \\
8 & Citigroup & United States & S\&P 500 \\
9 & Commerzbank & Germany & DAX 30 \\
10 & Credit Suisse & Switzerland & Swiss Market Index \\
11 & Deutsche Bank & Germany & DAX 30 \\
12 & HSBC & United Kingdom & FTSE 100 \\
13 & ING Groep & Netherlands & AEX \\
14 & JP Morgan Chase & United States & S\&P 500 \\
15 & KBC Groep & Belgium & BEL20 \\
16 & Lehman Brothers & United States & S\&P 500 \\
17 & Merrill Lynch & United States & S\&P 500 \\
18 & Morgan Stanley & United States & S\&P 500 \\
19 & National City Corporation & United States & S\&P 500 \\
20 & PNC Financial Services & United States & S\&P 500 \\
21 & Royal Bank of Scotland & United Kingdom & FTSE 100 \\
22 & Societe Generale & France & CAC 40 \\
23 & SunTrust Bank & United States & S\&P 500 \\
24 & U.S. Bancorp & United States & S\&P 500 \\
25 & UBS & Switzerland & Swiss Market Index \\
26 & UniCredit SPA & Italy & FTSE MIB \\
27 & Washington Mutual & United States & S\&P 500 \\
28 & Wells Fargo & United States & S\&P 500 \\
\hline
\multicolumn{4}{l}{Source: Own depiction based on Bloomberg database.}
\hline
\end{longtable}


\\missing. One after the\caption, the other after the "Source" multicolumn. – leandriis Aug 18 '19 at 10:12\multicolumn{4}{p{\textwidth-2\tabcolsep}}{<your descrition text>}\\in combination with thecalcpackage might give you the desired result. – leandriis Aug 18 '19 at 10:18booktabsfor horizontal lines with improved spacing. If you don't want to manually number the rows in your table, you might be interested in the following answer: https://tex.stackexchange.com/a/21245/134144 – leandriis Aug 18 '19 at 10:26