diff --git a/base/datafmt.jl b/base/datafmt.jl
index 5d36ed08c7d8d..c7790ca57eb2b 100644
--- a/base/datafmt.jl
+++ b/base/datafmt.jl
@@ -98,7 +98,7 @@ function store_cell(dlmoffsets::DLMOffsets, row::Int, col::Int, quoted::Bool, st
     if length(offsets) < offidx
         offlen = offs_chunk_size * length(oarr)
         if (offlen + offs_chunk_size) > dlmoffsets.thresh
-            est_tot = Int(offlen * dlmoffsets.bufflen / endpos)
+            est_tot = round(Int, offlen * dlmoffsets.bufflen / endpos)
             if (est_tot - offlen) > offs_chunk_size    # allow another chunk
                 # abandon offset collection
                 dlmoffsets.oarr = Vector{Int}[]