#!/usr/bin/env python2
 
from pylab import *
rc('xtick.major', pad = 8)
 
#from https://www.census.gov/foreign-trade/statistics/historical/gands.txt:
d = (3.508,  4.195,  3.370,  4.210,  6.022,  4.664,  2.939,  2.604,  0.250,
0.091,  2.254,  -1.302,  -5.443,  1.900,  -4.293,  12.404,  -6.082,  -27.246,
-29.763,  -24.565,  -19.407,  -16.172,  -24.156,  -57.767,  -109.072,
-121.880,  -138.538,  -151.684,  -114.566,  -93.141,  -80.864,  -31.135,
-39.212,  -70.311,  -98.493,  -96.384,  -104.065,  -108.273,  -166.140,
-263.160,  -376.749,  -361.771,  -417.432,  -490.984,  -605.357,  -708.624,
-753.288,  -696.728,  -698.338,  -379.154,  -494.737,  -559.880,  -540.362)
 
start, end = 1980, 2012
y = range(start, end + 1)
skip = start - 1960

f = figure(figsize = (7.5, 4.5))
ax = f.add_axes((.13, .18, .8, .75))
plot(y, d[skip:], 'r-', lw = 1.5)
plot(y, d[skip:], 'bo', ms = 5, mec = 'b')
grid(ls = '-', alpha = .4)

xlabel('Year')
ylabel('Billions USD')
title('U.S. Trade Balance')
 
text(end, -950, 'Data Source: US Census Bureau Foreign Trade Division',
  va = 'bottom', ha = 'right' , size = 10)
 
axis((start, end, -800, 0))
savefig("US Trade Balance %u %u.svg" % (start, end))
 
show()