A company's standard labor cost to produce one unit of a product is 15 hours at $12 per hour. During a period, 13,000 units were produced with actual labor costs amounting to $156,000. Evaluate the labor rate variance and labor efficiency variance, utilizing detailed analysis to identify the underlying causes of variance. Assess factors such as wage fluctuations, workforce productivity, and production scheduling on labor cost variances and develop strategies for cost optimization and variance reduction.