diff --git a/Makefile b/Makefile
index 6b06155..607956e 100644
--- a/Makefile
+++ b/Makefile
@@ -30,6 +30,10 @@ coverage:
 	CARGO_INCREMENTAL=0 RUSTFLAGS='-C instrument-coverage' LLVM_PROFILE_FILE='cargo-test-%p-%m.profraw' cargo test
 	grcov . --binary-path ./target/debug/deps/ -s . -t html --branch --ignore-not-existing --ignore '../*' --ignore "/*" -o target/coverage/html
 
+update-docs:
+	cargo build
+	./target/debug/documentation -o wiki/functions.md
+
 docs:
 	cargo doc --no-deps
 
diff --git a/wiki/functions.md b/wiki/functions.md
index 507113f..9fc9495 100644
--- a/wiki/functions.md
+++ b/wiki/functions.md
@@ -1,192 +1,192 @@
-AND
-FALSE
-IF
-IFERROR
-IFNA
-IFS
-NOT
-OR
-SWITCH
-TRUE
-XOR
-SIN
-COS
-TAN
-ASIN
-ACOS
-ATAN
-SINH
-COSH
-TANH
-ASINH
-ACOSH
-ATANH
-ABS
-PI
-SQRT
-SQRTPI
-ATAN2
-POWER
-MAX
-MIN
-PRODUCT
-RAND
-RANDBETWEEN
-ROUND
-ROUNDDOWN
-ROUNDUP
-SUM
-SUMIF
-SUMIFS
-CHOOSE
-COLUMN
-COLUMNS
-INDEX
-INDIRECT
-HLOOKUP
-LOOKUP
-MATCH
-OFFSET
-ROW
-ROWS
-VLOOKUP
-XLOOKUP
-CONCATENATE
-EXACT
-VALUE
-T
-VALUETOTEXT
-CONCAT
-FIND
-LEFT
-LEN
-LOWER
-MID
-RIGHT
-SEARCH
-TEXT
-TRIM
-UPPER
-ISNUMBER
-ISNONTEXT
-ISTEXT
-ISLOGICAL
-ISBLANK
-ISERR
-ISERROR
-ISNA
-NA
-ISREF
-ISODD
-ISEVEN
-ERROR.TYPE
-ISFORMULA
-TYPE
-SHEET
-AVERAGE
-AVERAGEA
-AVERAGEIF
-AVERAGEIFS
-COUNT
-COUNTA
-COUNTBLANK
-COUNTIF
-COUNTIFS
-MAXIFS
-MINIFS
-YEAR
-DAY
-MONTH
-EOMONTH
-DATE
-EDATE
-TODAY
-NOW
-PMT
-PV
-RATE
-NPER
-FV
-PPMT
-IPMT
-NPV
-MIRR
-IRR
-XIRR
-XNPV
-REPT
-TEXTAFTER
-TEXTBEFORE
-TEXTJOIN
-SUBSTITUTE
-ISPMT
-RRI
-SLN
-SYD
-NOMINAL
-EFFECT
-PDURATION
-TBILLYIELD
-TBILLPRICE
-TBILLEQ
-DOLLARDE
-DOLLARFR
-DDB
-DB
-CUMPRINC
-CUMIPMT
-BESSELI
-BESSELJ
-BESSELK
-BESSELY
-ERF
-ERF.PRECISE
-ERFC
-ERFC.PRECISE
-BIN2DEC
-BIN2HEX
-BIN2OCT
-DEC2BIN
-DEC2HEX
-DEC2OCT
-HEX2BIN
-HEX2DEC
-HEX2OCT
-OCT2BIN
-OCT2DEC
-OCT2HEX
-BITAND
-BITLSHIFT
-BITOR
-BITRSHIFT
-BITXOR
-COMPLEX
-IMABS
-IMAGINARY
-IMARGUMENT
-IMCONJUGATE
-IMCOS
-IMCOSH
-IMCOT
-IMCSC
-IMCSCH
-IMDIV
-IMEXP
-IMLN
-IMLOG10
-IMLOG2
-IMPOWER
-IMPRODUCT
-IMREAL
-IMSEC
-IMSECH
-IMSIN
-IMSINH
-IMSQRT
-IMSUB
-IMSUM
-IMTAN
-CONVERT
-DELTA
-GESTEP
-SUBTOTAL
\ No newline at end of file
+# List of Functions implemented in IronCalc\n* AND
+* FALSE
+* IF
+* IFERROR
+* IFNA
+* IFS
+* NOT
+* OR
+* SWITCH
+* TRUE
+* XOR
+* SIN
+* COS
+* TAN
+* ASIN
+* ACOS
+* ATAN
+* SINH
+* COSH
+* TANH
+* ASINH
+* ACOSH
+* ATANH
+* ABS
+* PI
+* SQRT
+* SQRTPI
+* ATAN2
+* POWER
+* MAX
+* MIN
+* PRODUCT
+* RAND
+* RANDBETWEEN
+* ROUND
+* ROUNDDOWN
+* ROUNDUP
+* SUM
+* SUMIF
+* SUMIFS
+* CHOOSE
+* COLUMN
+* COLUMNS
+* INDEX
+* INDIRECT
+* HLOOKUP
+* LOOKUP
+* MATCH
+* OFFSET
+* ROW
+* ROWS
+* VLOOKUP
+* XLOOKUP
+* CONCATENATE
+* EXACT
+* VALUE
+* T
+* VALUETOTEXT
+* CONCAT
+* FIND
+* LEFT
+* LEN
+* LOWER
+* MID
+* RIGHT
+* SEARCH
+* TEXT
+* TRIM
+* UPPER
+* ISNUMBER
+* ISNONTEXT
+* ISTEXT
+* ISLOGICAL
+* ISBLANK
+* ISERR
+* ISERROR
+* ISNA
+* NA
+* ISREF
+* ISODD
+* ISEVEN
+* ERROR.TYPE
+* ISFORMULA
+* TYPE
+* SHEET
+* AVERAGE
+* AVERAGEA
+* AVERAGEIF
+* AVERAGEIFS
+* COUNT
+* COUNTA
+* COUNTBLANK
+* COUNTIF
+* COUNTIFS
+* MAXIFS
+* MINIFS
+* YEAR
+* DAY
+* MONTH
+* EOMONTH
+* DATE
+* EDATE
+* TODAY
+* NOW
+* PMT
+* PV
+* RATE
+* NPER
+* FV
+* PPMT
+* IPMT
+* NPV
+* MIRR
+* IRR
+* XIRR
+* XNPV
+* REPT
+* TEXTAFTER
+* TEXTBEFORE
+* TEXTJOIN
+* SUBSTITUTE
+* ISPMT
+* RRI
+* SLN
+* SYD
+* NOMINAL
+* EFFECT
+* PDURATION
+* TBILLYIELD
+* TBILLPRICE
+* TBILLEQ
+* DOLLARDE
+* DOLLARFR
+* DDB
+* DB
+* CUMPRINC
+* CUMIPMT
+* BESSELI
+* BESSELJ
+* BESSELK
+* BESSELY
+* ERF
+* ERF.PRECISE
+* ERFC
+* ERFC.PRECISE
+* BIN2DEC
+* BIN2HEX
+* BIN2OCT
+* DEC2BIN
+* DEC2HEX
+* DEC2OCT
+* HEX2BIN
+* HEX2DEC
+* HEX2OCT
+* OCT2BIN
+* OCT2DEC
+* OCT2HEX
+* BITAND
+* BITLSHIFT
+* BITOR
+* BITRSHIFT
+* BITXOR
+* COMPLEX
+* IMABS
+* IMAGINARY
+* IMARGUMENT
+* IMCONJUGATE
+* IMCOS
+* IMCOSH
+* IMCOT
+* IMCSC
+* IMCSCH
+* IMDIV
+* IMEXP
+* IMLN
+* IMLOG10
+* IMLOG2
+* IMPOWER
+* IMPRODUCT
+* IMREAL
+* IMSEC
+* IMSECH
+* IMSIN
+* IMSINH
+* IMSQRT
+* IMSUB
+* IMSUM
+* IMTAN
+* CONVERT
+* DELTA
+* GESTEP
+* SUBTOTAL
diff --git a/xlsx/src/bin/documentation.rs b/xlsx/src/bin/documentation.rs
index ec19846..8055e4c 100644
--- a/xlsx/src/bin/documentation.rs
+++ b/xlsx/src/bin/documentation.rs
@@ -8,10 +8,19 @@ use std::fs;
 use ironcalc_base::model::Model;
 
 fn main() {
+    let args: Vec<_> = std::env::args().collect();
+    let output_file = if args.len() == 3 {
+        &args[2]
+    } else if args.len() == 1 {
+        "functions.md"
+    } else {
+        panic!("Usage: {} -o <file.md>", args[0]);
+    };
     let mut doc = Vec::new();
+    doc.push(r#"# List of Functions implemented in IronCalc\n"#.to_owned());
     for function in Model::documentation() {
-        doc.push(function.name);
+        doc.push(format!("* {}\n", &function.name));
     }
-    let data = doc.join("\n");
-    fs::write("functions.md", data).expect("Unable to write file");
+    let data = doc.join("");
+    fs::write(output_file, data).expect("Unable to write file");
 }