awk - Rounding to 2 decimal places in subtotals - awk

Question

Short version:
Is there a way to tell awk to round to 2 decimal places during the consolidation, not during the printing?
Long version:
I have an incoming file in the format below. I should get the net balances per currency and if the net is NOT zero, print the result in two columns: net balances less than zero go to neg_bal column and positive balances go to pos_bal column. For some reason, the USD column is still being printed despite netting to zero
JPY||170
JPY||40
USD|-42.61|
USD|-166.27
USD||42.61|
GBP|-20|
EUR||18.7
USD||174.6|
USD|-8.33||
EUR|-30.6|
GBP||100
JPY|-210|
Here is the code am using:
#!/bin/awk -f
BEGIN {
FS="|";
}
{
bal[$1]+=$2+$3
ccy[$1]=$1
}
END {
for (i in ccy)
{
if (bal[i] >0 )
{
pos_bal = bal[i]
neg_bal = 0
}
else
{
neg_bal = bal[i]
pos_bal = 0
}
if (bal[i] != 0 )
{
printf "%s|%.2f|%.2f\n",ccy[i],neg_bal,pos_bal
}
}
}
Result (notice JPY is not displayed since it nets to zero):
awk]$ ./scr1 file1
EUR|-11.90|0.00
USD|0.00|0.00
GBP|0.00|80.00
If I increase the decimal places to say, 20, I see that the USD net amount is not really zero. (Why is this, btw? Even excel gives a net of -1.59872E-14)
awk]$ ./scr1 file1
EUR|-11.90000000000000213163|0.00000000000000000000
USD|0.00000000000000000000|0.00000000000001243450
GBP|0.00000000000000000000|80.00000000000000000000

Answer 1

Is there a way to tell awk to round to 2 decimal places during the
consolidation, not during the printing?
Yes: multiply by 100 and convert to int. Then divide by 100 when you're ready to print.
(In other words, count pennies instead of dollars.)