Execution time about for-loops in Python

from timeit import default_timer as timer

# 1a. For-loop
position1 = 0
start = timer()
for i in range(1, 10**10):
    end = timer()
    elapsedTimeInMilliseconds = 1000 * (end - start)
    if elapsedTimeInMilliseconds >= 1000:
        position1 = i
        break


# 1b. Second for-loop
position2 = 0
start = timer()
for i in range(1, 10**10):
    end = timer()
    elapsedTimeInMilliseconds = 1000 * (end - start)
    if elapsedTimeInMilliseconds >= 2000:
        position2 = i
        break


# 2a. For-loop with conditions
position3 = 0
start = timer()
for i in range(1, 10**10):
    if i < 0 or i > 10**10:
        print("Error")
    end = timer()
    elapsedTimeInMilliseconds = 1000 * (end - start)
    if elapsedTimeInMilliseconds >= 1000:
        position3 = i
        break


# 2b. Second for-loop with conditions
position4 = 0
start = timer()
for i in range(1, 10**10):
    if i < 0 or i > 10**10:
        print("Error")
    end = timer()
    elapsedTimeInMilliseconds = 1000 * (end - start)
    if elapsedTimeInMilliseconds >= 2000:
        position4 = i
        break


# MAIN FUNCTION
percentage1 = (position1 - position3) / position1
percentage2 = (position2 - position4) / position2
percentage1 = int(10000 * percentage1) / 10000
percentage2 = int(10000 * percentage2) / 10000
print("******** Execution time = 1 second ********")
print(str(position1) + " simple iterations")
print(str(position3) + " iterations with conditions (" + str(100*percentage1) + "% less)")
print()
print("******** Execution time = 2 seconds ********")
print(str(position2) + " simple iterations")
print(str(position4) + " iterations with conditions (" +  str(100*percentage2) + "% less)")